NI 43-101 Technical Report

Definitive Feasibility Study and

Updated Mineral Reserve and Mineral Resource Estimates

Copper World Project

Pima County, Arizona, USA

Effective Date: September 30, 2026

25 York Street, Suite 800

Toronto, Ontario

Canada M5J 2V5

Prepared by:

Olivier Tavchandjian, P. Geo., Hudbay Minerals Inc.

CAUTIONARY NOTE REGARDING FORWARD-LOOKING INFORMATION

This Technical Report contains forward-looking information within the meaning of applicable Canadian and United States securities legislation. All information contained in this Technical Report, other than statements of current and historical fact, is forward-looking information. Often, but not always, forward-looking information can be identified by the use of words such as "plans", "expects", "budget", "guidance", "scheduled", "estimates", "forecasts", "strategy", "target", "intends", "objective", "goal", "understands", "anticipates" and "believes" (and variations of these or similar words) and statements that certain actions, events or results "may", "could", "would", "should", "might" "occur" or "be achieved" or "will be taken" (and variations of these or similar expressions). All of the forward-looking information in this Technical Report is qualified by this cautionary note.

Forward-looking information includes, but is not limited to, the results and findings of the 2026 Definitive Feasibility Study, including the production, operating cost, capital cost and cash cost estimates, the projected valuation metrics and rates of return, the cash flow and EBITDA projections, statements regarding the anticipated permitting requirements and project design, including processing and tailings facilities, metal recoveries, mine life and production rates for the Project, the expected funding requirements for the Project, the potential to further enhance the economics of the Project and optimize the design in the future, including with respect to the potential extension onto federal lands, as part of the Extension Case described herein and the potential to advance and possibly implement the concentrate leach option, the possibility of extending the life of the mine, and the expected social and environmental benefits of the Project, including with respect to the local communities and stakeholders. Forward-looking information is not, and cannot be, a guarantee of future results or events. Forward-looking information is based on, among other things, opinions, assumptions, estimates and analyses that, while considered reasonable by us at the date the forward-looking information is provided, inherently are subject to significant risks, uncertainties, contingencies and other factors that may cause actual results and events to be materially different from those expressed or implied by the forward-looking information.

The material factors or assumptions that Hudbay identified and were applied by Hudbay in drawing conclusions or making forecasts or projections set out in the forward-looking information include, but are not limited to:

• the ability to obtain and maintain all required permits and authorizations to develop and operate the Project in accordance with the Base Case presented in this Technical Report;

• the accuracy of the feasibility and pre-feasibility estimates of costs presented in this Technical Report;

• no capital cost escalation on the growth capital presented in this Technical Report due to inflationary or other factors;

• if a decision is made at a future date to pursue the Extension Case, the ability to obtain and maintain all additional permits and authorizations required to develop and operate the Project in accordance with the Extension Case presented in this Technical Report;

• the feasibility of aspects of the Base Case and Extension Case that to date have been completed to pre-feasibility levels;

• no delays or disruptions due to litigation challenging the permitting requirements or permits for the Project and no significant unanticipated litigation;

• the potential implementation of the concentrate leach option;

• the ability to acquire additional small parcels of land within Copper World's property boundary;

• the success of exploration and development activities;

• the accuracy of geological, mining and metallurgical estimates;

• anticipated metals prices and the costs of production;

• the supply and demand for metals the Project produces;

• the supply and availability of groundwater and surface water;

• the supply and availability of all forms of energy, fuels and other consumables at reasonable prices;

• no significant unanticipated operational or technical difficulties;

• the availability of additional financing, if needed;

• the stability of the joint venture partnership with Mitsubishi;

• the ability to complete Project targets on time and on budget;

• the availability of personnel for exploration, development and operational projects and ongoing employee relations;

• the ability to maintain good relations with the local communities, including the neighbouring communities and local governments in Arizona;

• no significant challenges with Pima County or other stakeholders at Copper World;

• no significant unanticipated events or changes relating to regulatory, environmental, health and safety matters;

• no contests over title to Hudbay's properties, including as a result of rights or claimed rights of Indigenous peoples or challenges to the validity of its unpatented mining claims;

• the ability to receive the upfront stream deposit of $230 million from Wheaton Precious Metals at the commencement of construction in accordance with the amended and restated precious metals purchase agreement;

• no disputes in respect of agreements that were previously entered into by Augusta Resource Corporation ("Augusta") in respect of the former Rosemont Copper Project;

• certain tax matters, including, but not limited to the mining tax regime in Arizona; and

• no significant and continuing adverse changes in general economic conditions or conditions in the financial markets (including commodity prices and foreign exchange rates).

The risks, uncertainties, contingencies and other factors that may cause actual results to differ materially from those expressed or implied by the forward-looking information may include, but are not limited to, risks generally associated with the mining industry and the current geopolitical environment, including future commodity prices, currency and interest rate fluctuations, water availability, energy and consumable prices, supply chain constraints and general cost escalation in the current inflationary environment, risks related to project delivery and financing; ongoing and potential litigation processes and other legal challenges that could affect the Project (including in respect of any future authorizations or agreements that may be required), risks related to acquiring additional small parcels of land within Copper World's property boundary, risks related to political or social instability and changes in government and government policy, risks related to changes in law, risks in respect of community relations, risks related to contracts that were entered into by Augusta in respect of the former Rosemont Copper Project, uncertainties related to the geology, continuity, grade and estimates of mineral reserves and resources, and the potential for variations in grade and recovery rates, risks related to the timing and implementation of the concentrate leach option, climate change related risks and uncertainties, as well as the risks discussed elsewhere in this Technical Report, under the heading "Risk Factors" in Hudbay's most recent annual information form and under the heading "Financial Risk Management" in Hudbay's most recent annual management's discussion and analysis, copies of which are available on Hudbay's SEDAR+ and EDGAR profiles. Should one or more risk, uncertainty, contingency or other factor materialize or should any factor or assumption prove incorrect, actual results could vary materially from those expressed or implied in the forward-looking information. Accordingly, you should not place undue reliance on forward-looking information. Hudbay does not assume any obligation to update or revise any forward-looking information after the date of this Technical Report or to explain any material difference between subsequent actual events and any forward-looking information, except as required by applicable law.

Cautionary Note Regarding NI 43-101

The scientific and technical information contained in this Technical Report has been approved by Olivier Tavchandjian, P. Geo, Hudbay's Senior Vice President, Exploration and Technical Services. Mr. Tavchandjian is a qualified person pursuant to Canadian Securities Administrators' National Instrument 43-101 - Standards of Disclosure for Mineral Projects ("NI 43-101").

This 2026 Definitive Feasibility Study is the current NI 43-101 Technical Report in respect of all of the mineral properties that form part of the Project and supersedes and replaces the 2023 PFS (as defined herein) in its entirety.

Readers should be advised that this Technical Report presents certain material information associated with the Project based on pre-feasibility level work only, which carries more risk and uncertainty than work completed to a feasibility study level. In addition, the Extension Case mine plan would require Copper World to apply for and obtain federal permits prior to Year 10 and is not the selected development option in this Technical Report. The Extension Case is intended to illustrate the full potential of the Project and in the opinion of the author constitutes other relevant data that should be included in this Technical Report. The Extension Case is based on measured and indicated mineral resources that are not mineral reserves.

Mineral resources that are not mineral reserves do not have demonstrated economic viability.

Non-IFRS Financial Performance Measures

This Technical Report contains certain non-IFRS financial performance measures. Cash cost and sustaining cash cost per pound of copper produced are shown because Hudbay believes they help investors and management assess the performance of its operations, including the margin generated by the operations and Hudbay. Unit operating costs are shown because Hudbay believes they help investors and management assess the cost structure and margins that are not impacted by variability in by-product commodity prices. EBITDA is shown to help users analyze Hudbay's results and to provide additional information about the company's ongoing cash generating potential in order to assess Hudbay's capacity to service and repay debt, carry out investments and cover working capital needs.

These measures and any other non-IFRS financial performance measures used herein do not have a meaning prescribed by IFRS and are therefore unlikely to be comparable to similar measures presented by other issuers. These measures should not be considered in isolation or as a substitute for measures prepared in accordance with IFRS and are not necessarily indicative of operating profit or cash flow from operations as determined under IFRS. Other companies may calculate these measures differently. For further details on these measures, please refer to Hudbay's most recent management's discussion and analysis, available on SEDAR+ at www.sedarplus.ca and EDGAR at www.sec.gov.

Cautionary Note to United States Investors

This Technical Report has been prepared in accordance with the requirements of the securities laws in effect in Canada, which differ from the requirements of United States securities laws. Canadian reporting requirements for disclosure of mineral properties are governed NI 43-101. For this reason, information contained in this Technical Report in respect of the Project may not be comparable to similar information made public by United States companies subject to the reporting and disclosure requirements under the United States federal securities laws and the rules and regulations thereunder. For further information on the differences between the disclosure requirements for mineral properties under the United States federal securities laws and NI 43-101, please refer to Hudbay's most recent annual information form, a copy of which has been filed under Hudbay's profile on SEDAR+ at www.sedarplus.ca and Hudbay's most recent Form 40-F, a copy of which has been filed on EDGAR at www.sec.gov.

Signature Page

This Technical Report titled "NI 43-101 Technical Report, Definitive Feasibility Study and Updated Mineral Reserve and Mineral Resource Estimates, Copper World Project, Pima County, Arizona, USA", dated October 20, 2026, and effective as of September 30, 2026, was prepared under the supervision and signed by the following author:

Dated this 20th day of October, 2026.

/s/ Olivier Tavchandjian

Signature of Qualified Person

Olivier Tavchandjian, P. Geo.

Senior Vice President, Exploration and Technical Services

Hudbay Minerals Inc.

Table of Contents

List of Tables

List of Figures

1 SUMMARY

1.1 Introduction

Hudbay Minerals Inc. ("Hudbay" or the "company") is a copper-focused critical minerals mining company with three long-life operations and a world-class pipeline of copper growth projects in tier-one mining jurisdictions of Canada, Peru, and the United States. Hudbay's mission is to create sustainable and strong returns by leveraging its core strengths in community relations, focused exploration, mine development, and efficient operations.

This Technical Report presents the results of a Definitive Feasibility Study (the "2026 Definitive Feasibility Study" or "DFS") supporting the initial investment, the results of two Pre-feasibility Studies supporting future investments in an expansion of the milling capacity and the installation of an in-pit crushing and conveying system, and the updated mineral reserve and mineral resource estimates of Hudbay's 70%-owned Copper World project (the "Project") in Pima County, Arizona, USA. The Project is currently held by Copper World LLC, an indirect subsidiary of Hudbay, that is 30% held indirectly by Mitsubishi Corporation ("Mitsubishi"). In January 2026, wholly owned subsidiaries of Hudbay and Mitsubishi, respectively, entered an Amended and Restated Limited Liability Company Agreement ("Joint Venture Agreement") that governs the parties' rights and obligations in respect of the Copper World joint venture. On closing of the Copper World joint venture transaction, Mitsubishi contributed approximately $420M of cash to Copper World LLC, and it will contribute an additional $180M in cash to complete its initial investment within 18 months of closing in accordance with the terms of the definitive transaction agreements. Mitsubishi will also fund its pro-rata 30% share of future equity capital contributions required to construct Copper World.

Following exploration success on its patented mining claims, in July 2022, Hudbay filed a Preliminary Economic Assessment (PEA) titled "Preliminary Economic Assessment, Copper World Project, Pima County, Arizona, USA", effective May 2022 (the "2022 PEA" or the "2022 Technical Report"). The 2022 PEA contemplated a two-phased mine plan with the first phase reflecting a standalone operation expected to require only state and local permits with an expected 16-year mine life. A second phase extended the mine life to 44 years through an expansion onto federal land that would require federal permits.

After completing additional technical studies, Hudbay filed a Pre-Feasibility Study (PFS) in September 2023 titled "Phase I Pre-Feasibility Study and Updated Mineral Resource Estimates Copper World Project Pima County, Arizona, USA", effective July 2023, (the "2023 PFS" or the "2023 Technical Report"). The 2023 PFS focused exclusively on the first phase of the anticipated operation, mining and processing of 385 Mt of ore and requiring only state and local permits over a 20-year mine life.

Since publishing the PFS, Hudbay has conducted limited drilling and focused recent technical work on metallurgical testing and progressing the engineering of the initial operation to a Feasibility Study level. Hudbay has also obtained all the major permits required to bring the mine into operation, secured Mitsubishi as its joint venture partner and completed several trade-off studies and de-risking activities. The principal changes since the 2023 PFS reflect optimization of the process flowsheet design, mine plan and tailings deposition strategy. This includes the addition of a future expansion of milling capacity from 60k to 90k short tons per day ("stpd") in Year 5 following the start of operations, the addition of an in-pit crushing and conveying system (IPCC) for ore haulage to be operational in Year 4 and conversion from conventional to dry stack tailings for approximately one third of the total volume of tailings deposition to start in Year 5.

The Base Case development option presented in this Technical Report (the "Base Case") and used to support the mineral reserve estimates contemplates a 15-year mine plan and is limited to a project exterior boundary and design that requires only state and local permits. The tonnage of ore mined and processed in the 2026 Definitive Feasibility Study is comparable to the 2023 PFS.

An Extension Case, based on measured and indicated mineral resource estimates only, is also presented in Sections 21, 22, 24 and 25 of the Technical Report (the "Extension Case"). The Extension Case contemplates an extension of mine activities onto Copper World's Unpatented Claims (as defined in Section 4 of this Technical Report) and associated lands in Year 10 and would require Copper World to apply for and obtain federal permits. The Extension Case extends the mine life to 37 years (plus two years of pre-stripping). The Extension Case is intended to illustrate some of the additional potential of the Project, but is not the selected development option for purposes of this Technical Report.

In addition, there is potential to further expand the mine life and/or the production capacity once the inferred mineral resource estimates and the exploration potential of the property are confirmed in future studies. The inferred mineral resource estimates are considered too speculative geologically to have the economic consideration applied to them that would enable them to be categorized as mineral reserves, and as a result, are treated as waste in this Technical Report.

Another change from the 2023 PFS is that the concentrate leach facility that would produce copper cathode at site has been removed from the current mine plan and presented as a future upside opportunity. Significant additional work has been done to establish the technical viability of the concentrate leach facility and it remains an option for the future. A summary of the test results and engineering work which have successfully progressed on this option, together with an economic analysis, are presented in Section 24 of this report.

This Definitive Feasibility Study demonstrates the economic viability of the proven and probable mineral reserve estimates. The mineral reserve and mineral resources estimate that retain potential for economic extraction, supersede and replace the estimates reported in the 2023 PFS.

This Technical Report includes measurements in both imperial and metric tons. All references to "tons" and "(short) tons" are to imperial tons and all references to "tonnes" are to metric tonnes. Please refer to the Unit Abbreviations in section 2 for further information.

All dollar amounts in this Technical Report are in US dollars, unless otherwise noted.

1.2 Property Description & Location

The Project is located within the historic Helvetia Mining District that dates to the 1800's. The deposit lies on the northern end and western foothills of the Santa Rita Mountain range 28 miles (45 km) southeast of Tucson, in Pima County, Arizona (Figure 1-1).

The property consists of a combination of fee land, leased land, patented mining claims, unpatented mining claims and mill sites, rights-of-way from the Arizona State Land Department, and grazing leases and permits. The Base Case presented in this Technical Report does not extend beyond the exterior boundary of Copper World's Patented Claims (as defined herein) and private landholdings, whereas the Extension Case contemplates mine activities beyond the exterior boundary and onto Copper World's Unpatented Claims and associated lands.

Precious metals production from the Project is subject to a stream agreement with Wheaton Precious Metals International Ltd. ("Wheaton"). Under the Wheaton stream agreement, Hudbay (BVI) International Inc. ("Hudbay BVI") is entitled to receive an initial deposit of $230M (subject to the satisfaction of certain conditions) against delivery of 92.5% of the gold and silver contained in the mineral products produced from the Project (other than any gold production that is less than 1g/t in concentrate during the first four years of operation), at fixed gold and silver prices of 15% of the market price. In addition, a contingent payment of up to $70M is payable to Hudbay BVI upon completion of the concentrator expansion to 90 kstpd by the fifth anniversary of commercial production, provided that a reduced contingent payment will nonetheless be payable if such expansion is completed by the tenth anniversary of commercial production. Hudbay BVI has entered into a stream agreement with Copper World LLC on substantially the same terms as the Wheaton stream agreement.

In addition, substantially all of the mining properties from which the minerals are contemplated to be extracted in the Base Case and Extension Case are subject to a 3% Net Smelter Returns (NSR) royalty.

Figure 1-1: Project Property Location

1.3 Geological Setting & Mineralization

The deposits are within the Laramide belt, a major porphyry province that includes several other world class deposits. Mesozoic subduction and associated magmatism and tectonism in the southwestern United States and northern Mexico generated extensive and relevant porphyry copper mineralization. Compressional tectonism during the Mesozoic and early Cenozoic Laramide Orogeny caused folding and thrusting, accompanied by extensive calc-alkaline magmatism. Tertiary faulting juxtaposed mineralized and unmineralized rocks in large-scale block faulting that produced the present basin and range geomorphology that is typical throughout southern Arizona.

The Project is in the northern block of the Santa Rita Mountains, dominated by Precambrian granite with slices of Paleozoic and Mesozoic sediments, and small stocks and dikes of quartz monzonite or quartz latite porphyry that are related to porphyry copper and skarn mineralization. Tertiary faulting has significantly segmented the original stratigraphy, juxtaposing mineralized and unmineralized rocks. Mineralization occurs as both copper oxides and sulfides in skarns, and intrusive porphyry.

1.4 Deposit Types

Genetically, skarns form part of the suite of deposit styles associated with porphyry copper centers. The skarns were formed as the result of thermal and metasomatic alteration of Paleozoic carbonate and, to a lesser extent, Mesozoic clastic rocks. Near-surface weathering has resulted in the oxidation of the sulfides in the overlying Mesozoic units at the East Deposit, and near-surface Paleozoic units at Copper World.

Mineralization is mostly in the form of primary (hypogene) copper, molybdenum, and silver bearing sulfides, found in stockwork veinlets, and disseminated in the altered host rock at depth. Near the surface, along structural zones, and in quartzite units, oxidized copper mineralization is present. The oxidized mineralization occurs as mixed copper oxide and copper carbonate minerals. Enriched supergene chalcocite rich zones associated with secondary mineralization are found in and beneath the oxidized mineralization.

1.5 Exploration

Prospecting began in the Helvetia-Rosemont Mining District in the mid-1800s, and by 1875, copper production was first recorded, which continued sporadically until 1951. By the late 1950s, exploration drilling had discovered the East Deposit. A succession of major mining companies subsequently conducted exploratory drilling focused on the East Deposit and the nearby Broadtop Butte and Peach-Elgin mineralized areas.

Two infill drilling campaigns were completed by Hudbay around the East Deposit in 2014 and 2015. In addition to chemical assaying, magnetic susceptibility and conductivity measurements were also taken. Hudbay analyzed all samples of the 2014 and 2015 drilling programs with ICP multi-element geochemistry. This new geochemical data set was used to model stratigraphy and geochemical attributes and proved to be a useful tool for geological modeling and vectoring.

In October 2020, Hudbay resumed exploration drilling on targets at its Copper World private land claims located north and west of the East Deposit. The drill program has continued until present, focusing mostly on the Peach, Elgin, West and Broadtop Butte areas, as well as establishing the continuity to the East Deposit through the Bolsa area.

1.6 Drilling, Sample Preparation, Analytical Procedures & Data Validation

All available data from both historical and modern drilling was consolidated for inclusion in the geological model for the 2023 PFS (Table 1-1). Drilling activities at site resumed in 2024 with a focus on geotechnical and condemnation drilling. Some limited infill drilling activities were also initiated in 2025, mostly in the West and Broadtop Butte areas as operational readiness activities. No resource model update was undertaken since the 2023 PFS as the recent drilling is very limited and not deemed to have any material impact on the Definitive Feasibility Study mine plan. Out of a total of 1,754 drill holes used for the 2023 resource model, 1,277 holes have intersected copper mineralization and were used to define the mineralized envelopes for the Copper World and East Deposits.

Sample preparation, security, and analytical procedures used by Augusta and Hudbay since 2005 meet current industry accepted standards. QA/QC procedures including the use of certified reference material, blanks and interlaboratory checks on pulp duplicates have resulted in acceptable precision, accuracy, and contamination level. Statistical comparisons and database entry checks of older historical drilling data did not identify any significant biases or database quality issues. Specific gravity was measured in laboratories using water displacement on core and validated with box weight measurements to derive in-situ density estimates for each mineralization domain.

Independent data verification by Hudbay was conducted under the supervision of Olivier Tavchandjian, Hudbay's Senior Vice President, Exploration and Technical Services, and a Qualified Person pursuant to NI 43-101, and it is the opinion of the author that the quality of the data is suitable for use in resource calculations and that sampling to date is representative of the deposit.

Table 1-1: Summary of Drilling Used for the Resource Model

1.7 Mineral Processing & Metallurgical Testing

The metallurgical flowsheet developed for the Project is technically robust, commercially viable, and features low risk across all evaluated ore zones. Key findings establish that a standard crushing, grinding and flotation flowsheet achieves high copper recoveries, produces clean and marketable concentrates, and defines clear environmental pathways for tailings and water management.

The metallurgical baseline was established upon four major modern testing campaigns completed between 2014 and 2026, which built upon older historical work from 1974 to 2013. Since the 2023 PFS, feasibility-level validation work was conducted by BML, SGS, AMinpro, McLelland Labs, Glencore Technology, and TailPro to further define, quantify, and de-risk the mineralogical and metallurgical relationships across all the deposits included in the mine plan. Testing utilized a comprehensive suite of production period composites and geometallurgical subtype composites. These samples cover all lithogeochemical domains and mining envelopes, ensuring excellent spatial and grade representativity.

Ore hardness is well-defined across all deposits through an extensive database consisting of 727 variability samples tested to quantify SAG mill resistance, Ball milling energy requirements as well as SMC, Ball mill and bond impact crusher work index measured from composited samples. The hardness metrics were integrated into the resource block model using Random Forest algorithms from multi-element geochemical data, achieving high predictive R² values for the 727 test results and enabling high confidence in throughput modelling.

An extensive quantitative mineralogical database was established using automated mineralogy (QEMSCAN and TIMA-X on over 1,000 samples), Cation Exchange Capacity (CEC), Fourier Transform Near-Infrared Spectroscopy (FTNIR), and X-ray Diffraction (XRD). The primary mineralogical drivers are copper deportment through primary and secondary sulfides transitioning to copper silicates, carbonates, oxides, goethite and wads, talc and clays composition and the abundance of pyrite. To map these mineralogical drivers across the resource block model, predictive models were developed using Random Forest algorithms. These models utilize multi-element geochemical assays to estimate quantitative mineral concentrations, resolving complex, non-linear geological relationships. The resulting machine learning models demonstrate high correlation coefficients (R²) against measured automated mineralogy.

The current flotation protocol replaces historical simple xanthate schemes with a highly effective Controlled Potential Sulfidization (CPS) approach. Standard primary grind followed by sulfidization will maintain an oxidation-reduction potential target. Extensive test work was also conducted to establish the optimum regrind circuit target for the overall cleaner feed. To prevent overgrinding of clays, a cyclone classification circuit has been added to bypass fine material ahead of the regrind mill.

Locked-cycle tests across all campaigns have confirmed the stability of the circuit operation as well as the ability to produce marketable concentrates and to successfully upgrade precious metals into the final copper concentrate.The copper/molybdenum separation was also validated on combined concentrates.

The Project concentrates are clean and highly marketable. Standard penalty elements (lead, zinc, arsenic, bismuth, and mercury) generally remain below smelter penalty limits, while Fluorine was identified as the primary deleterious element. Mineralogical analysis shows that only 10% to 20% of fluorine-bearing minerals (micas, fluorite, apatite) are physically locked with sulfides or talc; the rest report via physical mechanical entrainment. Controlling entrainment, using low-entrainment flotation technology (Jameson Cells), is key to maintaining concentrate grades and keeping fluorine below penalty limits.

Concentrate leaching using the Albion Process™ was also shown to be highly effective, and while it is not included in the Base Case, it is shown as a future upside opportunity in Section 24 of this Technical Report. Extraction kinetics conducted since 2023 have achieved 97% to 99% copper extraction within 36 to 48 hours at atmospheric pressure and 95°C.

1.8 Mineral Resource Estimates

The mineral resource models constructed for the Project have been prepared under the supervision of Mr. Olivier Tavchandjian P. Geo. and a Qualified Person pursuant to a NI 43-101. Mr. Tavchandjian is Hudbay's Senior Vice President, Exploration and Technical Services. The mineral resource estimates have been updated based on the revised economic and technical parameters of the Project presented in this Technical Report. The estimates comply with CIM Definition Standards for Mineral Resources and Mineral Reserves (May 10, 2014). The resource modelling and classification methodology applied by Hudbay for the Project is similar and fully consistent with those used at its operating mines and remains unchanged since the 2023 PFS with the exception of the addition of predictive models for material hardness and flotation recovery based on random forest algorithms developed from multi-element geochemical assay results. The flotation predictive model includes the estimated deportment of copper for 6 types of minerals as well as an estimate of abundance of pyrite, talc and swelling clays to ensure their compliance with the future process plant feed requirements.

Hudbay used three-dimensional models of lithological units and mineralization envelopes constructed in Leapfrog Geo™ software using an 'implicit modelling' approach. A wireframe model of the 0.10% copper (Cu) grade shell was also constructed in Leapfrog Geo™. The selection of this copper grade threshold for modelling was based on visual inspection of the spatial and statistical grade distribution. The grade shell includes mineralization grading less than 0.10% Cu where it was deemed necessary to maintain a smooth and continuous three-dimensional envelope. The different lithological units were grouped into four structural domains which were further divided into mineralized envelopes based on the dominance of oxide or sulfide copper mineralization within the 0.10% Cu grade shell. These domains were verified to be also consistent with the main drivers for grinding flotation performance.

Drill core assay intervals for copper (Cu), molybdenum (Mo), silver (Ag), and gold (Au) as well as for all the geochemical elements used for the predictive models of hardness and flotation performance were composited down hole into a fixed length of 25 ft (7.5 m). Composite intervals with lengths less than 12.5 ft (4 m) were appended to the previous composite. The composite intervals were back-tagged with a copper grade-shell code based on the wireframe models to be used during grade estimation. Visual checks were conducted to ensure back-tagging worked as expected.

Exploratory Data Analysis (EDA), including industry standard statistical analysis and variography was undertaken within each mineralized envelope to help develop a plan for block grade estimation.

The block model consists of non-rotated regular blocks of 50 x 50 x 50 ft (15 x 15 x 15 m) as a reasonable proxy for the anticipated Selective Mining Unit (SMU) during open-pit mining. The proportion of the individual blocks within each envelope was estimated using the wireframes prepared in Leapfrog™. A dry bulk density was assigned based on the volume of the block inside each envelope based on the mean value of in-situ density measured from core box weights and validated with laboratory measurements.

The Cu, Mo, Ag, and Au block grade values as well as those elements used in the geometallurgical model were interpolated using an Ordinary Kriging (OK) estimator with a three-pass estimation approach with each successive pass having greater search distances and less restrictive sample selection requirements. A firm boundary approach within each mineralized envelope was employed for all metals.

The block model grade estimates were validated by Hudbay geologists through visual inspection comparing composite grades to block grades, statistical checks, and selectivity checks. During its review, Hudbay identified an opportunity to reduce the inherent smoothing of the kriged model. This correction was implemented separately by mineralized envelope based on grade distribution and by areas with consistent drilling density. In each block, the weighted average grade was calculated using the interpolated grade estimate by envelope properly weighted by the volume and density within each envelope.

A Lerchs-Grossman analysis was performed using the block models constructed by Hudbay. Several economic analyses were developed for nested pit shells. The purpose of this assessment was to evaluate free discounted cash flow, revenue, stripping ratio, development, sustaining capital, and as guidance for internal phases, recoveries by processing route and by deposit. The base-case pit shell retained for resource reporting corresponds to a revenue factor of 1.0 with an assumed copper price of $5/lb to ensure potential for economic extraction of the mineral resource estimates.

Table 1-2 shows the mineral resource estimates inclusive of mineral reserve estimates and tabulated within the resource pit shell at a NSR cut-off value of $6.03/st.

Table 1-2: Mineral Resource Statement (Inclusive of Mineral Reserves)

Notes: 1. CIM Definition Standards (2014) were used for reporting the Mineral Resources. 2. Numbers may not compute exactly due to rounding. 3. The Qualified Person is Olivier Tavchandjian. 4. Mineral Resources are estimated as of 1st August 2026. 5. An NSR cut-off value of $6.03/st. was used to define material as ore. 6. Mineral resource estimates are inclusive of mineral reserves and have been tested using pit optimization software with the following assumptions: metal prices of US$5.00/lb Cu, US$20.00/lb Mo, US$3,600/oz Au, and US$50.00/ oz Ag; operating costs of US$1.61/st, US$5.34/st processed, G&A costs of US$0.69/st processed; metallurgical recovery rates vary according to elemental content, and are based on preliminary metallurgical test work. 7. Mineral resources are not mineral reserves as they do not have demonstrated economic viability.

Table 1-3 summarizes the mineral resource estimates exclusive of the measured and indicated mineral resource estimates that have been converted to mineral reserve estimates in Section 1.9. These mineral resource estimates include resource estimates in all categories located inside a pit shell with revenue factor of 1.0 and outside of the mineral reserve pit as well as mineral resource estimates located within the mineral reserve pit not processed within the mine life of the Definitive Feasibility Study and as such excluded from the mineral reserve estimates but still deemed to have potential for economic extraction with additional infill drilling and/or additional metallurgical test work.

Table 1-3: Mineral Resource Statement (Exclusive of Mineral Reserves)

Notes: 1. CIM Definition Standards (2014) were used for reporting the Mineral Resources. 2. Numbers may not compute exactly due to rounding. 3. The Qualified Person is Olivier Tavchandjian. 4. Mineral Resources are estimated as of 1st August 2026. 5. An NSR cut-off value of $6.03/st. was used to define material as ore. 6. Mineral resource estimates are exclusive of mineral reserves and have been tested using pit optimization software with the following assumptions: metal prices of US$5.00/lb Cu, US$20.00/lb Mo, US$3,600/oz Au, and US$50.00/ oz Ag; operating costs of US$1.61/st, US$5.34/st processed, G&A costs of US$0.69/st processed; metallurgical recovery rates vary according to elemental content, and are based on preliminary metallurgical test work. 7. Mineral resources are not mineral reserves as they do not have demonstrated economic viability.

Table 1-4 presents a comparison of the previous mineral resource estimates (inclusive of mineral reserve estimates) presented in the 2023 PFS and the 2026 Definitive Feasibility Study mineral resource estimates. The mineral resource estimates provided in the 2023 PFS have been superseded by those presented in this Technical Report as part of the 2026 Definitive Feasibility Study. Overall, the changes between the 2023 and 2026 mineral resource estimates inclusive of the mineral reserve estimates represent the changes in the technical and economic criteria used to report resources, i.e., use of a NSR cut-off replacing a copper cut-off, updated metal price, use of a new flotation recovery formulation and removal of the leachable mineral resource estimates. The change in copper metal contained in the measured and indicated mineral resource estimates is negligible while the metal content in inferred mineral resource estimates has increased by 5%. The overall reduction in headgrade can be explained by the replacement of high-grade leachable resources at low recoveries by lower grade flotation resources but with an estimated higher processing recovery. 

Table 1-4: Comparison of 2023 vs 2026 Mineral Resource Estimates

Note: 1. Totals may not add up correctly due to rounding.

In the opinion of the author, the construction of the mineral resource model is consistent with the CIM Estimation of Mineral Resources and Mineral Reserves Best Practice Guidelines. The modelling and grade estimation process used is appropriate for a skarn/porphyry-style copper-molybdenum-silver-gold deposit and the resource model is suitable to support mine planning for a large-scale open pit mine. The assumptions used in 2026 to assess reasonable prospects of eventual economic extraction, including metal prices, mining, processing and G&A cost and metallurgical recoveries, are also all considered reasonable by the author.

Other than the risks identified in this Technical Report, the author is not aware of any other environmental, permitting, legal, title, taxation, socioeconomic, marketing, political, or other relevant factors that could materially affect the mineral resource estimate.

1.9 Mineral Reserve Estimate

The Mineral Reserve block model is based on the Mineral Resource model described in Section 14. The Resource block model was re-blocked into a regularized 50'x50'x50' Reserve block model. This block size is considered appropriate for the selective mining unit (SMU) size applicable in the envisioned open pit mining operation. This regularization is deemed to introduce sufficient 'internal dilution' into the Reserve mining model to cover all dilution and ore loss ascribed to the ore feed. No further modifying factors have been applied.

Mineral Resources are converted to Mineral Reserves through the demonstration of positive economics following an engineering assessment involving pit optimization, pit design, equipment selection, scheduling and economic evaluation. As was the case in the 2023 PFS, in the Base Case, the conversion of Measured and Indicated Mineral Resources to Mineral Reserves within the limit of the reserve pit is limited to 390 million tonnes due to tailings storage limitations.

The mineral reserves estimation is based on the Base Case mine plan including only measured and indicated mineral resource estimates. The inferred mineral resource estimates within the mineral reserve pit are reported as waste, as they currently do not meet the economic and mining requirements to be categorized as mineral reserves. It cannot be assumed that all or any part of inferred mineral resources will ever be upgraded to a higher category.

Proven and probable mineral reserve estimates for the Project are summarized in Table 1-5. Proven and probable mineral reserves within the designed final pit of the base case total 390 million tonnes of material, grading 0.47% Cu, 103g/tonne Mo, 5.1 g/tonne Ag, and 0.023 g/tonne Au. The total material excavated from the pit is approximately 990 million tonnes.

The mineral reserves estimate presented in this Technical Report is dependent on market prices for the contained metals, metallurgical recoveries and ore processing, mining, and general/administration cost estimates. Mineral reserve estimates in subsequent evaluations of the Copper World deposits may vary according to changes in these factors. Other than the risks identified in this Technical Report, there are no other known mining, metallurgical, infrastructure or other relevant factors that may materially affect the mineral reserve estimates.

The 2026 mineral reserve estimates present a comparable tonnage at a lower average copper grade than the 2023 PFS mineral reserve estimates which were reported at 385 million tonnes at 0.54% Cu. The reduction in grade relates to a change in mine planning strategy aiming at an approximately 20% smaller pit compared to the 2023 PFS, resulting in a significant reduction in the strip ratio. As the space for tailings and waste rock disposal is the main constraint on mine planning in the Base Case, the significant reduction in the strip ratio offsets the loss in metal production while also considering the impact of a new flotation recovery formulation and updated metal price forecast and cost assumptions. The higher-grade mineralization to be recovered at the expense of more waste excavation is not lost and is later recovered in the mine plan of the Extension Case which is not subject to the same land constraints for waste and tailings disposal.

Table 1-5: Proven & Probable Mineral Reserves Total - Final Pits

Notes: 1. CIM Definition Standards (2014) were used for reporting the Mineral Reserves. 2. Numbers may not compute exactly due to rounding. 3. The Qualified Person is Olivier Tavchandjian. 4. Mineral Reserves are estimated as of 1st August 2026. 5. An NSR cut-off value of $5.80/st. was used to select material for processing. A minimum Cu grade of 0.1% and a minimum Cu recovery of 48% were also applied due to the limited tailings capacity.

1.10 Mining Methods

The Copper World Project will employ conventional open-pit, truck-and-shovel mining methods across four primary pits: East, Broadtop, West, and Peach-Elgin. The overall mine plan integrates essential supporting infrastructure, including waste rock facilities (WRFs), grade-segregated ore stockpiles, a tailings storage facility (TSF), and IPCC system (refer to Figure 1-2). Mining operations are scheduled to run continuously, 24 hours per day, 365 days per year.

Under the Base Case mine plan, total production encompasses 390 million tonnes of ore and approximately 589 million tonnes of waste, yielding a life-of-mine (LOM) strip ratio of 1.5:1 (waste-to-ore), inclusive of pre-production stripping. The Base Case establishes a 15-year LOM, in addition to a two-year pre-stripping period. Economic material will be delivered to a conventional flotation plant for processing.

Mill throughput is designed to ramp up to 60 kstpd over the initial seven months of Year 1, followed by a planned expansion to 90 kstpd in Year 5. The production schedule prioritizes the extraction and processing of higher-margin material early in the LOM. Lower-grade material is routed to grade-segregated stockpiles and reclaimed opportunistically to optimize mill feed grades and satisfy blending parameters.

A combined pit optimization process was completed for the four deposits to evaluate overarching economic potential and establish an indicative mining sequence that explicitly incorporates spatial constraints. For the Base Case, the ultimate pit limits were selected to maximize resource extraction based on baseline economic assumptions, while remaining strictly confined within the exterior boundary of the currently permitted footprints for mining, WRFs, and the TSF.

Open pit design parameters are predicated on the selected mining equipment, operating strategy, and geotechnical slope stability criteria. To ensure achievable production schedules and constrain pushback sequencing, the vertical advance rate is capped at 10 benches per year. Haul road dimensions are designed to minimize overall strip ratios while maintaining strict safety standards to accommodate both staffed and Autonomous Haulage System (AHS) fleet operations.

The Base Case mining schedule encompasses 13 distinct pushback phases. This sequence targets high-grade, low-strip-ratio mineralization early in the LOM while smoothing the waste-stripping profile to ensure continuous ore exposure.

Figure 1-2: Base Case Layout of the Mining Infrastructures

The operation is configured for large-scale mining on 50-foot benches. Primary loading will utilize Caterpillar 6060 hydraulic shovels and 995 front-end loaders. Haulage will be conducted by a fleet of 320-ton AHS Caterpillar 794 trucks operating on dual-lane ramps. Drilling will be executed by Caterpillar MD6310 and Epiroc D65LF rotary blast hole drills, supported by a fleet including Caterpillar D10 track dozers, 24M motor graders, and 777 water carts.

To efficiently manage high material tonnages, an IPCC system is integrated into the East Pit. Scheduled to become operational in Year 4, the system will convey ore from the East Pit directly to the processing plant and stockpiles. The IPCC features a 91 kstpd nominal capacity gyratory crusher, permanently located at the southern end of the Broadtop Phase 3 pit. Its implementation is paired with a sequential pit-backfill strategy that facilitates WRF expansion.

Waste rock will be stored in designated WRFs and within the exhausted Peach-Elgin, Broadtop, and West pits. Material will be end-dumped in 100-foot lifts, with crests set back and dozed to target angles for concurrent reclamation. The WRF design provides sufficient storage capacity, including 45 Mt specifically designated for TSF construction.

Due to strict property boundary constraints, 3D block-modeled stockpiles with a nominal capacity of approximately 100 Mt were designed to optimize ore handling and grade segregation. This stockpiling strategy ensures a continuous supply of full-capacity mill feed during high-strip-ratio periods while preserving long-term Mineral Reserves.

The Base Case mine production schedule consists of the following main periods:

• Pre-production period: A two-year phase (Year -2 and Year -1) during which the owner-operated mining fleet will execute pre-stripping activities.

• Steady-Stage and Expansion: Production is maintained at 60 kstpd until the mill is expanded to 90 kstpd in Year 5.

Figure 1-3: Mine Production Over the Base Case Life of Mine Plan

The Extension Case evaluates a brownfield extension featuring a conceptual 37-year LOM (plus two years of pre-stripping). This Extension scenario contemplates the extraction of approximately 1,048 Million tonnes of mill feed and 1,880 Million tonnes of waste. Under this plan, the private land-type constraints of the Base Case are relaxed after Year 10, provided operations remain within the broader boundaries of Hudbay's Unpatented Claims. Four additional mining phases in the East Deposit support this extended LOM.

The Measured and Indicated Mineral Resources incorporated into the Extension Case require the use of federal lands outside the current Project perimeter. The Extension Case is not the selected development option and would require Copper World to apply for and obtain federal permits, including completion of a NEPA process that has not yet been initiated, prior to Year 10.

Figure 1-4 displays the mine production and material movement over the Extension Case 37-year life of mine plan (plus two years of pre-stripping.

Figure 1-4: Mine Production Over the Extension Case Life of Mine Plan

Overburden and other waste rock exposed during mining will be placed into the Waste Rock Facilities (WRF). Upon completion of mining activities in the Peach-Elgin, Broadtop, and West pits, these areas will be utilized for long-term waste rock storage. Waste will be end-dumped in 100 ft high lifts with dump faces at the angle of repose. The WRF crests will be set back to allow simple dozing of the crests down to meet the target re-graded slope angles to support concurrent reclamation. The current Waste Rock Facilities (WRF) design integrates an IPCC in the construction sequence, providing sufficient storage capacity including ~50Mt to be routed to the tailings storage facility.

1.11 Project Infrastructure

The Project infrastructure consists of access and plant roads, a processing complex, electric power supply and distribution, water supply and distribution, an IPCC system, voice and data communication, waste rock and tailings storage facilities, and other ancillary facilities.

Access to the Project area is through South Santa Rita Road, at the point between South Nogales Highway and South Country Club Road on East Sahuarita Road, in the Town of Sahuarita, Pima County, Arizona. The Project's primary access road will intersect Santa Rita Road and give entrance to the in-plant roads, haul roads and other roads used to access the facilities.

The initial development phase centers on a 60 kstpd concentrator plant that processes a mix of primary and secondary copper sulfides with some other copper bearing minerals using conventional crushing, grinding, flotation, molybdenum separation, concentrate dewatering, and tailings thickening. It includes a two-stage cyclone station used to produce sand for TSF dam construction. The concentrator expansion intentionally avoids wholesale replacement or resizing of active operating equipment. Instead, throughput and production increases are achieved via parallelization and modular additions of proven commercial technologies. This design methodology lowers technical execution risk, simplifies constructability, minimizes operational downtime during tie-ins, and offers a clear, staged progression for the Project's lifecycle. An in-pit crushing and conveyance system is also added and operational in Year 4.

Tucson Electric Power (TEP) will provide service via a 138 kV transmission line connected at the proposed Toro Switchyard located in Hudbay's private land parcel (Sanrita South). The power system is designed to support the 60 kstpd base case concentrator, the 90 kstpd throughput expansion, the IPCC expansion, and tailings expansions (and also has the capacity to support a concentrate leach facility in the future).

The water supply source identified for the Project is groundwater from the Santa Cruz Basin, which lies west of the Project and the Santa Rita Mountains. Hudbay has a permit to withdraw groundwater for mineral extraction and metallurgical processing in the amount of 6,000 acre-feet per year (which is currently set to expire in January 2028 but is renewable for successive 20-year terms). Fresh water is treated at a dedicated site water treatment facility, supplying offices, change houses, and safety showers. Potable storage accommodates 48 hours of average consumption. Process Water is sourced primarily from tailings thickener overflow and supplemented with site stormwater/process pond run-off. The site water management system separates clean stormwater from contact process water to minimize treatment requirements and protect regional groundwater. Data networking and telecommunication systems will be integrated into a common infrastructure. Mobile radio will also be used by the mine and plant operation personnel for daily control and communications while outside the offices.

The Project includes the construction of three Tailings Storage Facilities in the Base Case scenario: TSF-1, TSF-2, and the southern portion of the area designated as TSF-N. The Extension Case assumes TSF-N is not built and includes two other TSFs in addition to TSF-1 and TSF-2. Tailings management incorporates both conventional (hydraulic) deposition and filtered tailings dry stacking. Foundations were conservatively modeled as alluvial/colluvial soil. Slope stability was evaluated under static (drained/undrained) and pseudo-static loading conditions. All safety factors meet or exceed the design limits specified by the Arizona Department of Environmental Quality (ADEQ) Best Available Demonstrated Control Technology (BADCT) Guidance Manual and are designed in accordance with the CIM TSM tailings standards.

The Waste Rock Facilities (WRF), will receive waste rock from the pits, starting from the west side area. The WRF will be large enough to contain the estimated 589 million tonnes of waste rock generated from within the proposed limits of the pits for the Base Case. In the Extension Case, an additional WRF would be established in close proximity to the East Pit. Stability was evaluated under static and pseudo-static conditions using limit equilibrium methods on critical cross-sections for circular and non-circular slip surfaces. Waste rock is classified as predominantly non-acid generating (NAG), presenting a negligible risk of acid mine drainage.

Other site buildings have been centralized in order to optimize security, administrative communication, and utility distribution. These additional infrastructures include: truck shop, welding shop, tire workshop, mine offices & warehouse, emergency response facility, security & gatehouses, laydown and logistics, fuel storage and change house facilities.

1.12 Marketing

The Project will produce saleable metals in the form of copper and molybdenum concentrates.

Pursuant to the terms of the Joint Venture Agreement, Hudbay is entitled to 70% of the copper and molybdenum concentrate production from the Project and Mitsubishi is entitled to the remaining 30%. Each partner will enter into an offtake agreement with Copper World LLC to purchase its pro rata share of the concentrates on the same, industry standard, terms.

Global copper concentrate fundamentals are expected to be strong in the medium/longer term.

Smelters globally are expected to seek significant metal production to attempt to satisfy the expected increase in demand driven by, among other things, the electrification megatrend, in particular to support the rapid expansion of Artificial Intelligence (AI) datacentres. However, smelters' ability to do so may be constrained by a shortage of mine production.

Global markets are expected to compete aggressively for concentrate supply, providing a strong market for sales of the Copper World concentrate.

While copper will be the main product sold, Copper World will also produce molybdenum concentrate as a byproduct.  Medium/long term fundamentals for molybdenum are forecast to be constructive. Regionally, the US will continue to import molybdenum concentrate, as it does now from locations such as South America.  Consequently, Copper World production is expected to be absorbed regionally, in part helping to satisfy growing molybdenum oxide demand related to the reshoring of the US manufacturing base.

Table 1-6 provides a summary of the commodity price assumptions used in the economic evaluation of the Project.

Table 1-6: Commodity Price Assumption

Notes: 1. Commodity price assumptions in the table represent long-term prices starting in Year 3 of operations. Price assumptions in Year 1 and Year 2 of operations are as follows: copper $5.50/lb and $5.13/lb, gold $3,788/oz and $3,638/oz, silver $46.25/oz and $45/oz, molybdenum $17.50/lb in both years. 2. Gold and silver stream based on 15% of the market price as stipulated in the stream agreement with Wheaton, estimated at $540/oz for gold based on $3,600/oz gold price assumption and $6.75/oz silver based on $45/oz silver price assumption.

1.13 Environmental Studies, Permitting, & Social or Community Impact

As part of both current and past project activities, numerous surveys and studies related to the biological and cultural aspects of the site have been completed. Additionally, the geochemical characterization of site materials has been performed along with groundwater and surface water studies.

The Base Case presented in this Technical Report only requires state, county, and local permits.  Federal authorizations are required for the Extension Case.

State, county, and local permits have been delivered from the following agencies:

• Arizona Corporation Commission (ACC)

• Arizona Department of Environmental Quality (ADEQ)

• Arizona Department of Water Resources (ADWR)

• Arizona State Mine Inspector (ASMI)

• Pima County

• Town of Sahuarita

All the major permits required for the construction and start of operations have been issued and are set out below. Certain permit amendments and renewals will be required in the normal course after the Project commences operations.

• Groundwater Withdrawal Permit (issued by ADWR)

• Arizona Mined Land Reclamation Plan (issued by ASMI)

• Class II Air Quality Control Permit (issued ADEQ)

• Aquifer Protection Permit (APP) (issued ADEQ)

• Certificate of Environmental Compatibility (CEC) (for powerline, issued to TEP by the ACC)

• Floodplain Use Permit (FUP) (for waterline within utility corridor, issued by Pima County)

Permit modifications will be required to incorporate the IPCC, the concentrator expansion to 90 kstpd and the filtered tailings facility.

The Project will include conventional tailings disposal with three tailings storage facilities. The Project will meet the Arizona Department of Environmental Quality (ADEQ) Best Available Demonstrated Control Technology (BADCT) requirements (includes facilities such as the Waste Rock Facility, and Tailings Storage Facilities). Equipment specifications, such as for dust collector efficiency, will be part of permit requirements for an air quality control permit issued by ADEQ. Additionally, monitoring and reporting requirements will be required for most of the permits associated with the Project.

Regarding community outreach and other social commitments, specific allocations will be determined as the Project progresses and the community is further engaged. Additionally, Hudbay is committed to the preservation of historical and cultural resources as well as the protection of endangered and other protected species.

Hudbay actively integrates stakeholder and public feedback from permit comment periods into its ongoing mitigation planning, maintaining a dedicated cost allowance within the Project's financial model. Cultural resources are protected via rigorous pre-disturbance field surveys and site management plans.

The net economic benefit of the Project is estimated at $1,126M for the Base Case, considering only total U.S. taxes over the life of mine, including $200M to the State of Arizona and $362M in local property taxes. It is anticipated to generate over 750 construction jobs, 500 permanent operating roles, and up to 3,000 indirect employment opportunities within Arizona.

Hudbay is responsible for reclamation of surface disturbances attributed to the Project. Reclamation and closure of private lands are regulated by ADEQ and ASMI. Closure and reclamation bonding is apportioned amongst the agencies as applicable.

The project is backed by a comprehensive $137.8M closure and reclamation strategy. Financial assurance is fully secured from the initiation of project construction via the surety market. Requisite bonds are maintained at an annual premium fee of 1% of the total notional value. Post-closure maintenance plans commit to a 5-year reclamation success monitoring window alongside tailing drain-down solution management that can extend up to 30 years.

1.14 Capital & Operating Costs

1.14.1 Base Case Capital and Operating Costs

Total life of mine capital costs of $3,463M consist of $2,070M initial growth, $710M expansionary growth, $484M sustaining and $199M capitalized stripping costs. Costs are presented in 2026 dollars, unless stated otherwise, and are reflected net of equipment financing. 

Growth capital includes two phases of construction. The first phase consists of the mine, 60 kstpd concentrator process plant, and related infrastructure totalling $2,070M to be incurred during the 12 quarters prior to production in 2029. The second phase consists of optimizations including the molybdenum processing plant, IPCC and concentrator expansion to 90 kstpd. The molybdenum processing plant is planned for Year 1 of operations and totals $25M.  The IPCC is operational in Year 4 of operations to optimize hauling and rehandling costs as the mine operations approach the East Pit and totals $242M. The concentrator expansion is completed in Year 4 of operations to expand the daily processing capacity to 90 kstpd starting the following year, incorporating additional equipment and construction and totals $443M.

The technical studies for the concentrator expansion and IPCC have each been done to a pre-feasibility level of engineering. The expansionary growth capital estimates for each of these projects are subject to a higher degree of uncertainty than the initial growth capital for the Base Case, which has been done to a feasibility level of engineering.

Sustaining capital of $484M is primarily mining-related costs of the waste rock facility, tailings facility, major repairs and overhauls and haul roads, as well as sustaining costs related to plant and general administrative facilities.  Capitalized stripping of $199M is composed of capitalized mine operating costs for stripping applicable to the portion of the annual strip ratio in excess of the life of mine strip ratio.

The unit operating costs used in this Definitive Feasibility Study are summarized in Table 1-7. Mining cost is presented on a total cost basis over tonnes of material moved and on an operating cost basis excluding capitalized stripping. Processing and Onsite G&A are presented on a per tonne of feed milled basis.

Table 1-7: Base Case - Unit Operating Cost Summary

1.14.2 Extension Case Capital and Operating Costs

In the Extension Case, total life of mine capital costs of $4,657M consist of $2,070M initial growth, $1,105M expansionary growth, $878M sustaining and $604M capitalized stripping costs. Costs are presented in 2026 dollars, unless otherwise stated, and are reflected net of equipment financing.

Growth capital costs are comparable to the Base Case, and also include expanded filtered tailings growth capital of $395M starting in Year 10 of operations.

Sustaining capital of $878M is primarily mining-related costs of the waste rock facility, tailings facility, major repairs and overhauls and haul roads, as well as sustaining costs related to plant and general administrative facilities, and reflects the extension of mine life to 37 years.  Capitalized stripping of $604M is composed of capitalized mine operating costs for stripping applicable to the portion of the annual strip ratio in excess of the life of mine strip ratio.

The unit operating costs for the Extension Case are summarized in Table 1-8. Mining cost is presented on a total cost basis over tonnes of material moved and on an operating cost basis excluding capitalized stripping. Processing cost and Onsite G&A are presented on a per tonne of feed milled basis.

Table 1-8: Extension Case - Unit Operating Cost Summary

1.15 Economic Analysis

1.15.1 Base Case Economic Analysis

Based on the Cash Flow Model results, the Base Case has an unlevered after-tax NPV8% and NPV10% of $1,241M and $845M respectively, an after-tax IRR of 16.8%, a payback period of 5.4 years (including investment in the molybdenum processing plant in Year 1, in the IPCC in Year 3 and in the concentrator expansion to 90 kstpd in Year 4), and an annual average EBITDA of $566M at a long-term copper price of $5.00/lb of copper.

The average annual copper production is 95,000 tonnes over a 15-year mine life (excluding pre-stripping), at average cash costs and sustaining cash costs of $1.70 and $2.21 per pound of copper, respectively. The higher average annual production in Years 6 to 10 is due to the concentrator expansion. In the Base Case, the annual copper production drops after year 10 due to a declining mill feed grade while it is maintained at comparable levels for a long period in the Extension case. The IPCC and concentrator expansion to 90 kstpd are based on pre-feasibility level engineering, carry a higher degree of uncertainty, and require permit amendments not yet obtained.

Key valuation, production, and cost details from the Base Case are summarized in Table 1-9.

Table 1-9: Base Case - Summary of Project Key Valuation Metrics

Notes: 1. Calculated assuming the following long-term commodity prices: copper price of $5.00 per pound ($5.50 per pound in year 1 and $5.13 per pound in year 2), gold stream price of $540 per ounce (15% of market price), silver stream price of $6.75 per ounce (15% of market price), and molybdenum price of $17.50 per pound. Reflects the terms of the amended Wheaton stream agreement, including an upfront deposit of $230 million in the first year of construction in exchange for the delivery of 92.5% of gold and silver contained in the mineral products produced (other than any gold production that is less than 1g/t in concentrate during the first four years of operation), followed by an additional deposit of up to $70 million upon successful completion of the concentrator expansion to 90,000 short tons per day by the fifth anniversary of commercial production (provided that a reduced contingent payment will nonetheless be payable if such expansion is completed by the tenth anniversary of commercial production). 2. Copper production includes copper contained in concentrate sold. Average annual copper production excludes partial year of production in Year 15. 3. EBITDA is a non-GAAP financial performance measure with no standardized definition under IFRS. For further information, please refer to the company's most recent Management's Discussion and Analysis for the three and six months ended June 30, 2026. 4. By-product credits calculated using amortization of deferred revenue for gold and silver stream sales as per the Company's approach in its quarterly financial reporting. Sustaining cash cost includes sustaining capital expenditures and royalties. Cash cost and sustaining cash cost are non-GAAP financial performance measures with no standardized definition under IFRS. For further information, please refer to the Company's most recent Management's Discussion and Analysis for the three and six months ended June 30, 2026.

1.15.2 Extension Case Economic Analysis

Based on the Cash Flow Model results, the Extension Case has an unlevered after-tax NPV8% and NPV10% of $2,510M and $1,685M respectively, an after-tax IRR of 18.8%, a payback period of 5.4 years (including investment in the molybdenum processing plant in Year 1, the IPCC in Year 3, and concentrator expansion to 90 kstpd in Year 4), and an annual average EBITDA of $522M at a long-term copper price of $5.00/lb of copper. Annual EBITDA is higher in the first 20 years, averaging $684M.

The average annual copper production is 89,000 tonnes over a 37-year mine life, at average cash costs and sustaining cash costs of $1.94 and $2.38 per pound of copper, respectively. Annual copper production is higher in the first 20 years, averaging 109,000 tonnes.

The Extension Case is based on measured and indicated mineral resources that are not mineral reserves. Mineral resources that are not mineral reserves do not have demonstrated economic viability.

Key valuation, production, and cost details from the Extension Case are summarized in Table 1-10.

Table 1-10: Extension Case - Key Metrics of the Financial Analysis

Notes: 1. Calculated assuming the following long-term commodity prices: copper price of $5.00 per pound ($5.50 per pound in year 1 and $5.13 per pound in year 2), gold stream price of $540 per ounce (15% of market price), silver stream price of $6.75 per ounce (15% of market price), and molybdenum price of $17.50 per pound. Reflects the terms of the amended Wheaton stream agreement, including an upfront deposit of $230 million in the first year of construction in exchange for the delivery of 92.5% of gold and silver contained in the mineral products produced from the Project (other than any gold production that is less than 1g/t in concentrate during the first four years of operation), followed by an additional deposit of up to $70 million upon successful completion of the concentrator expansion to 90,000 short tons per day by the fifth anniversary of commercial production (provided that a reduced contingent payment will nonetheless be payable if such expansion is completed by the tenth anniversary of commercial production). 2. Payback period does not include filtered tailings capital in Years 10 and 11. 3. Copper production includes copper contained in concentrate sold. 4. EBITDA is a non-GAAP financial performance measure with no standardized definition under IFRS. For further information, please refer to the Company's most recent Management's Discussion and Analysis for the three and six months ended June 30, 2026. 5. By-product credits calculated using amortization of deferred revenue for gold and silver stream sales as per the Company's approach in its quarterly financial reporting. Sustaining cash cost includes sustaining capital expenditures and royalties. Cash cost and sustaining cash cost are non-GAAP financial performance measures with no standardized definition under IFRS. For further information, please refer to the Company's most recent Management's Discussion and Analysis for the three and six months ended June 30, 2026.

1.16 Conclusions and Recommendations

This Technical Report describes a Base Case mine plan, as well as the operating cost and capital cost estimates and economic analysis supporting the Base Case and the methodology and assumptions used in support of the mineral resource and mineral reserve estimates update. In addition, an Extension Case including the extension of mining activities on Federal land starting in Year 10 is also presented in this report to illustrate the full potential of the project albeit still limited to only including the current measured and indicated mineral resource estimates for the Project.

In the Base Case, the mining sequence considers the exploitation of the pits and their associated infrastructure over a footprint expected to require only state and local permits for 15 years (plus two years of pre-stripping). During this period, all waste, tailings, and low-grade stockpiles are also disposed of within the perimeter of Hudbay's private land properties. An important constraint on the mine production schedule is the limited space for disposing of waste rocks, tailings, and low-grade stockpiles, resulting in a sub-optimum mining sequence from a strict economic standpoint. However, the current mine plan allows the mine to operate in a sustainable manner for 15 years. Securing Federal permits earlier would unlock significant benefits to the project by removing these important constraints on the mining schedule and likely allow more tons and/or better grades to be mined earlier than currently planned. This is illustrated in the Extension Case which has assumed that mining activities could progress onto Federal land in Year 10.

The mill consists of conventional crushing, grinding, flotation, molybdenum separation, concentrate dewatering and tailings dewatering. Comprehensive metallurgical testwork completed across four major campaigns demonstrates that the proposed process flowsheet for the Copper World Project is strong across the evaluated ore domains and variability suites. The Project produces a clean, marketable copper concentrate averaging approximately 24 % Cu over the life of mine, accompanied by payable precious metals credits. A dual-phase tailings management plan-transitioning from conventional hydraulic disposal (cyclone sand embankment raises and slimes thickening) to having a portion of whole tailings pressure filtered for dry stacking- has been validated and defined with robust engineering design criteria.

For more information on the interpretations and conclusions associated with this Definitive Feasibility Study, please refer to Section 25 of this Technical Report.

For more information on the recommendations associated with this Definitive Feasibility Study, please refer to Section 26 of this Technical Report.

2 INTRODUCTION AND TERMS OF REFERENCE

2.1 General

Hudbay Minerals Inc. ("Hudbay" or the "company") is a copper-focused mining company with three long-life operations and a world-class pipeline of copper growth projects in tier-one mining-friendly jurisdictions of Canada, Peru, and the United States. Hudbay's mission is to create sustainable and strong returns by leveraging its core strengths in community relations, focused exploration, mine development, and efficient operations.

This Technical Report presents the results of the 2026 Definitive Feasibility Study, the results of two Pre-feasibility Studies supporting future growth investments in both mill and mine production, and the updated mineral reserve and mineral resource estimates of Hudbay's 70%-owned Copper World project (the "Project") in Pima County, Arizona, USA. The Project is currently held by Copper World LLC, an indirect subsidiary of Hudbay, that is 30% held indirectly by Mitsubishi. In January 2026, Hudbay and Mitsubishi entered into a Joint Venture Agreement that governs the parties' rights and obligations in respect of the Copper World joint venture.

The Base Case development option presented in this Technical Report and used to support the mineral reserve estimates contemplates a 15-year mine plan and is limited to the project outer boundary and design that requires only state and local permits.

An Extension Case, based on measured and indicated mineral resource estimates only, is also presented in Sections 21, 22, 24 and 25 of the Technical Report (the "Extension Case"). The Extension Case contemplates an extension of mine activities beyond the current outer boundary and onto Copper World's Unpatented Claims (as defined herein) and the associated federal lands in Year 10 and would require Copper World to apply for and obtain federal permits. The Extension Case is intended to illustrate the full potential of the Project, but is not the selected development option for purposes of this Technical Report.

This 2026 Definitive Feasibility Study demonstrates the economic viability of the proven and probable mineral reserve estimates. The mineral reserve estimates and the mineral resource estimates that retain potential for economic extraction, supersede and replace the mineral resource and mineral reserve estimates reported in the 2023 Technical Report.

2.2 Terms of Reference

This Technical Report conforms with the 2014 CIM Definition Standards and the requirements of NI 43-101.

Notwithstanding that the Technical Report has an effective date of September 30, 2026, the mineral resource and mineral reserve estimates contained in this Technical Report are estimated as of August 1, 2026.

Additional drilling collected since 2023 has focused on collecting geotechnical information to support engineering studies and condemnation drilling, with also some limited infill drilling of the areas as preparation for pre-stripping activities. The cut-off date for drilling assay results used in the 2023 resource model was March 1, 2023, and remains unchanged for the 2026 Definitive Feasibility Study.

Additional mineralogical studies and metallurgical test work have been conducted since 2023 on material collected at all the deposits included in the scope of this Definitive Feasibility Study to confirm the operating parameters of the flotation processing flow sheet.

The capital costs, sustaining capital costs, and operating costs have been reviewed and updated to reflect the current plan, and are expressed in 2026 dollars.

All illustrations (including Maps and Figures) that have been included in this Technical Report shall be deemed to be dated as of the effective date of this Technical Report and prepared by Hudbay unless expressly stated otherwise.

2.3 Qualified Person

The Qualified Person responsible for the preparation of this Technical Report is Olivier Tavchandjian, P. Geo., Hudbay's Senior Vice President, Exploration and Technical Services. Mr. Tavchandjian is not independent from Hudbay.

Mr. Tavchandjian made multiple site visits to the property to maintain familiarity with conditions on the property, to observe the geology and mineralization, and to verify the work completed on the Project. Mr. Tavchandjian has also reviewed and conducted sufficient confirmatory work to act as the Qualified Person for the reporting of the mineral resource and mineral reserve estimates for the Project.

2.4 Site Visits & Responsibility

Site visits to the Project have been completed as shown in Table 2-1. Mr. Tavchandjian, while on site, reviewed the site property, project office, and drilled core samples that remain at site, as well as visiting two external laboratories that were used for the drill campaigns since 2020.

Additional senior personnel of Hudbay involved in the preparation of this document are Chris Marion (Senior Manager Metallurgy Services), Steve Cashin (Vice President Mineral Processing and Operational Excellence) Warren Flannery (Vice President and Head, Arizona Business Unit), Kim Hackney (Copper World Project Director), Clarissa Barazza (Project Associate Managing Director), Jon Leblanc (Chief Financial Officer, US Business Unit) and Steve Hayes (Vice President Marketing). Their involvement in this Technical Report is detailed in Table 3-1.

Table 2-1: Dates of Recent Project Site Visits

2.5 Unit Abbreviations

The units of measure in this Technical Report are a combination of US standard units and metric units. Unit abbreviations used are noted below in Table 2-2.

Table 2-2: Unit Abbreviations

2.6 Name Abbreviations

Abbreviations of company names, chemical terms, and general terms used in this Technical Report are as shown in Table 2-3.

Table 2-3: Name Abbreviations

3 RELIANCE ON OTHER EXPERTS

The information, conclusions, opinions, and estimates contained herein are based on:

• Information available to Hudbay at the time of preparation of this Technical Report, and

• Assumptions, conditions, and qualifications as set forth in this Technical Report.

Table 3-1: Reliance on Other Experts

4 PROPERTY DESCRIPTION & LOCATION

4.1 Location

The Project is located within the historical Helvetia Mining District that dates to the 1800's. The deposits lie on the northern end and western foothills of the Santa Rita Mountain range approximately 28 miles (45 km) southeast of Tucson, in Pima County, Arizona, USA. The subject areas include T17S R13E (Section 36); T17S R14E (Sections 17, 21, 24, 29, and 31); T17S R15E (Section 35). T18S R15E (Sections 2, 10, 11, 13-15, 22-27, and 36); and T18S R16E (Sections 1, 14, 15, 19, 21, 23, 27, and 29-32). Finally, the southernmost sections are located in T19S R15E (Sections 1 and 23) and T19S R16E (Sections 16, 17, and 21) all in the Gila & Salt River Meridian, Pima County, Arizona. The Project geographical coordinates are approximately 31º 86'N and 110º 77'W.

Access to the Project is from Santa Rita and Helvetia Roads from the west and Highway 83, over and across Forest Service roads from the east.

Figure 4-1: Project Property Ownership

4.2 Tenure

The property consists of a combination of fee land, leased land, patented mining claims, unpatented claims, rights-of-way from the Arizona State Land Department, and grazing leases and permits (Figure 4-1).

The core of the Project mineral resource is contained within the 132 patented mining claims that encompass an area of 2,003.46 acres (811 hectares) (the "Patented Claims"). Surrounding the Patented Claims is a contiguous package of 2,099 unpatented and mill-site claims with an aggregate area of more than 22,416 acres (9,072 hectares) (the "Unpatented Claims"). Associated with the Patented Claims and other claims are 81 parcels of land consisting of approximately 5,444.62 acres (2,203 hectares) (the "Associated Lands"). The area covered by the Patented Claims, Unpatented Claims and Associated Lands totals approximately 29,864 acres (12,086 hectares).

The Base Case presented in this Technical Report does not extend beyond the exterior boundary of Copper World's Patented Claims and private landholdings and, as such, the Base Case only requires state and local permits. The Extension Case contemplates extending mine activities beyond the exterior boundary of Copper World's Patented Claims and onto Copper World's Unpatented Claims and the associated federal lands. There are a limited number of small parcels of land that Copper World intends to acquire to consolidate landholdings and optimize the operation.

The federal lands covered by Unpatented Claims are accessible under the provisions of the Mining Law of 1872, subject to approval in accordance with the surface use regulations of the U.S. Forest Service ("USFS") and the Bureau of Land Management ("BLM") and in compliance with the National Environmental Policy Act ("NEPA"). Copper World has not yet applied for these federal approvals.

A table of the legal descriptions, location and acreages of the Patented Claims, Unpatented Claims and Associated Lands is provided Table 4-1, Table 4-2 and Table 4-3.

Table 4-1:  Patented Claims - Description and Location