Description of Business and Summary of Significant Accounting Policies	6 Months Ended
Jun. 30, 2025
Accounting Policies [Abstract]
Description of Business and Summary of Significant Accounting Policies	1. Description of Business and Summary of Significant Accounting Policies1.1. Description of Business Unless the context otherwise requires, or unless indicated otherwise, “we”, “us”, “our”, “Smurfit Westrock” and “the Company” refer to the business of Smurfit Westrock plc, its wholly-owned subsidiaries and its partially-owned consolidated subsidiaries. Smurfit Westrock plc is a company limited by shares that is incorporated in Ireland. We are a multinational provider of sustainable fiber-based paper and packaging solutions. We partner with our customers to provide differentiated, sustainable paper and packaging solutions that enhance our customers’ prospects of success in their markets. Our team members support customers around the world from our operating and business locations in North America, South America, Europe, Asia, Africa, and Australia. 1.2. Basis of Presentation We derived the Condensed Consolidated Balance Sheet at December 31, 2024 from the audited consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024 (the “2024 Consolidated Financial Statements”). In the opinion of management, all normal recurring adjustments necessary for a fair statement of the Condensed Consolidated Financial Statements have been included for the interim periods reported. The accompanying Unaudited Condensed Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the U.S. (“GAAP”) for interim financial information and with Article 10 of Regulation S-X of the Securities and Exchange Commission (“SEC”). Accordingly, they omit certain notes and other information from the 2024 Consolidated Financial Statements. Therefore, these Condensed Consolidated Financial Statements should be read in conjunction with the 2024 Consolidated Financial Statements. The results for the three and six months ended June 30, 2025 are not necessarily indicative of results that may be expected for the full year. The preparation of the Condensed Consolidated Financial Statements in conformity with U.S. GAAP requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the Condensed Consolidated Financial Statements, disclosures about gain contingencies and contingent liabilities and the reported amounts of revenues and expenses, including income taxes during the reporting period. Such estimates include the fair value of assets acquired and assumed liabilities in a business combination, determining goodwill and measuring impairment, income taxes and pension and other postretirement benefits. These estimates and assumptions are based on management’s judgment. Actual results may differ from those estimates, and the differences could be material. We base our estimates on the current information available, our experiences and various other assumptions believed to be reasonable under the circumstances. The process of determining significant estimates is fact specific and takes into account factors such as historical experience, current and expected economic conditions, product mix, and in some cases, actuarial techniques. We regularly evaluate these significant factors and make adjustments in the Condensed Consolidated Financial Statements where facts and circumstances dictate. Due to rounding, numbers presented throughout this document may not add up precisely to the totals provided and percentages may not precisely reflect the absolute figures. 1.3. Supplier Finance Program Obligations We maintain supplier finance programs whereby we have entered into payment processing agreements with certain financial institutions. These agreements allow participating suppliers to track payment obligations from Smurfit Westrock, and if voluntarily elected by the supplier, to sell payment obligations from Smurfit Westrock to financial institutions at a discounted price. We are not a party to the agreements between the participating financial institutions and the suppliers in connection with the program, and we do not reimburse suppliers for any costs they incur for participation in the program. We have not pledged any assets as security or provided any guarantees as part of the programs. We have no economic interest in our suppliers’ decisions to participate in the programs. Our responsibility is limited to making payment in full to the respective financial institution according to the terms originally negotiated with the supplier, which generally do not exceed 120 days. Smurfit Westrock or the financial institutions may terminate the agreements upon 30 or 90 days’ notice. These obligations are classified as accounts payable within the Condensed Consolidated Balance Sheets. The outstanding payment obligations to financial institutions under these programs were $375 million and $450 million as of June 30, 2025 and December 31, 2024, respectively. 1.4. Significant Accounting Policies There have been no changes to the Company’s significant accounting policies as described in “Note 1. Description of Business and Summary of Significant Accounting Policies” in the 2024 Consolidated Financial Statements, other than as noted below. 1.5. Impairment and Restructuring Costs When we close a facility, if necessary, we recognize a write-down to reduce the carrying value of related property, plant and equipment and lease right-of-use (“ROU”) assets to their fair value and record charges for severance and other employee-related costs. For termination costs associated with employees covered by a written or substantive plan, a liability is recorded when it is probable that employees will be entitled to benefits and the amount can be reasonably estimated. For termination costs associated with employees not covered by a written and broadly communicated policy covering involuntary termination benefits (severance plan), a liability is recorded for costs to terminate employees (one-time termination benefits) when the termination plan has been approved and committed to by management, the employees to be terminated have been identified, the termination plan benefit terms are communicated, the employees identified in the plan have been notified and actions required to complete the plan indicate that it is unlikely that significant changes to the plan will be made or that the plan will be withdrawn. The timing and amount of an accrual is dependent upon the type of benefits granted, the timing of communication and other provisions that may be provided in the benefit plan. If property, plant and equipment become impaired as a result of the Company’s restructuring efforts, these assets are written down to their fair value less costs to sell, as the Company commits to dispose of them, and they are no longer in use. Depreciation is accelerated on property, plant and equipment for the period of time the asset continues to be used until the asset ceases to be used. For facility closures, we also generally expect to record costs for equipment and inventory relocation, facility carrying costs and costs to terminate a lease or contract before the end of its term. Identifying and calculating the cost to exit operations requires certain assumptions to be made, the most significant of which are anticipated future liabilities, including severance costs, contractual obligations, and the adjustments of property, plant and equipment and lease ROU assets to their fair value. Our estimates are reasonable, considering our knowledge of the industry we operate in, previous experience in exiting activities and valuations we may obtain from independent third parties. 1.6. New Accounting Standards Recently Adopted During the six months ended June 30, 2025, there were no newly issued or newly applicable accounting pronouncements adopted that had, or are expected to have, a material impact on the Condensed Consolidated Financial Statements. 1.7. New Accounting Standards Not Yet Adopted In December 2023, the FASB issued ASU 2023-09, “Income Taxes (Topic 740): Improvements to Income Tax Disclosures.” This ASU requires the annual financial statements to include consistent categories and greater disaggregation of information in the rate reconciliation, and income taxes paid disaggregated by jurisdiction. ASU 2023-09 is effective for the Company’s annual reporting periods beginning after December 15, 2024. Adoption is either with a prospective method or a retrospective method of transition. Early adoption is permitted. The new disclosures (as required) will be included in the consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025. In November 2024, the FASB issued ASU 2024-03, “Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses” (“ASU 2024-03”). This ASU requires new financial statement disclosures disaggregating prescribed expense categories within relevant income statement expense captions. ASU 2024-03 will be effective for fiscal years beginning after December 15, 2026, and interim periods beginning after December 15, 2027. Adoption is either with a prospective method or a retrospective method of transition. Early adoption is permitted. The Company is currently evaluating the impact of this standard on its disclosures in the consolidated financial statements.

Description of Business and Summary of Significant Accounting Policies

6 Months Ended

Jun. 30, 2025

Description of Business and Summary of Significant Accounting Policies

1. Description of Business and Summary of Significant Accounting Policies1.1. Description of Business

Unless the context otherwise requires, or unless indicated otherwise, “we”, “us”, “our”, “Smurfit Westrock” and “the Company” refer

to the business of Smurfit Westrock plc, its wholly-owned subsidiaries and its partially-owned consolidated subsidiaries.

Smurfit Westrock plc is a company limited by shares that is incorporated in Ireland. We are a multinational provider of sustainable

fiber-based paper and packaging solutions. We partner with our customers to provide differentiated, sustainable paper and packaging

solutions that enhance our customers’ prospects of success in their markets. Our team members support customers around the world

from our operating and business locations in North America, South America, Europe, Asia, Africa, and Australia.

1.2. Basis of Presentation

We derived the Condensed Consolidated Balance Sheet at December 31, 2024 from the audited consolidated financial statements

included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024 (the “2024 Consolidated Financial

Statements”). In the opinion of management, all normal recurring adjustments necessary for a fair statement of the Condensed

Consolidated Financial Statements have been included for the interim periods reported.

The accompanying Unaudited Condensed Consolidated Financial Statements have been prepared in accordance with accounting

principles generally accepted in the U.S. (“GAAP”) for interim financial information and with Article 10 of Regulation S-X of the

Securities and Exchange Commission (“SEC”). Accordingly, they omit certain notes and other information from the 2024

Consolidated Financial Statements. Therefore, these Condensed Consolidated Financial Statements should be read in conjunction with

the 2024 Consolidated Financial Statements. The results for the three and six months ended June 30, 2025 are not necessarily

indicative of results that may be expected for the full year.

The preparation of the Condensed Consolidated Financial Statements in conformity with U.S. GAAP requires management to make

certain estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the Condensed Consolidated

Financial Statements, disclosures about gain contingencies and contingent liabilities and the reported amounts of revenues and

expenses, including income taxes during the reporting period. Such estimates include the fair value of assets acquired and assumed

liabilities in a business combination, determining goodwill and measuring impairment, income taxes and pension and other

postretirement benefits. These estimates and assumptions are based on management’s judgment. Actual results may differ from those

estimates, and the differences could be material.

We base our estimates on the current information available, our experiences and various other assumptions believed to be reasonable

under the circumstances. The process of determining significant estimates is fact specific and takes into account factors such as

historical experience, current and expected economic conditions, product mix, and in some cases, actuarial techniques. We regularly

evaluate these significant factors and make adjustments in the Condensed Consolidated Financial Statements where facts and

circumstances dictate.

Due to rounding, numbers presented throughout this document may not add up precisely to the totals provided and percentages may

not precisely reflect the absolute figures.

1.3. Supplier Finance Program Obligations

We maintain supplier finance programs whereby we have entered into payment processing agreements with certain financial

institutions. These agreements allow participating suppliers to track payment obligations from Smurfit Westrock, and if voluntarily

elected by the supplier, to sell payment obligations from Smurfit Westrock to financial institutions at a discounted price. We are not a

party to the agreements between the participating financial institutions and the suppliers in connection with the program, and we do

not reimburse suppliers for any costs they incur for participation in the program. We have not pledged any assets as security or

provided any guarantees as part of the programs. We have no economic interest in our suppliers’ decisions to participate in the

programs. Our responsibility is limited to making payment in full to the respective financial institution according to the terms

originally negotiated with the supplier, which generally do not exceed 120 days. Smurfit Westrock or the financial institutions may

terminate the agreements upon 30 or 90 days’ notice. These obligations are classified as accounts payable within the Condensed

Consolidated Balance Sheets.

The outstanding payment obligations to financial institutions under these programs were $375 million and $450 million as of June 30,

2025 and December 31, 2024, respectively.

1.4. Significant Accounting Policies

There have been no changes to the Company’s significant accounting policies as described in “Note 1. Description of Business and

Summary of Significant Accounting Policies” in the 2024 Consolidated Financial Statements, other than as noted below.

1.5. Impairment and Restructuring Costs

When we close a facility, if necessary, we recognize a write-down to reduce the carrying value of related property, plant and

equipment and lease right-of-use (“ROU”) assets to their fair value and record charges for severance and other employee-related costs.

For termination costs associated with employees covered by a written or substantive plan, a liability is recorded when it is probable

that employees will be entitled to benefits and the amount can be reasonably estimated. For termination costs associated with

employees not covered by a written and broadly communicated policy covering involuntary termination benefits (severance plan), a

liability is recorded for costs to terminate employees (one-time termination benefits) when the termination plan has been approved and

committed to by management, the employees to be terminated have been identified, the termination plan benefit terms are

communicated, the employees identified in the plan have been notified and actions required to complete the plan indicate that it is

unlikely that significant changes to the plan will be made or that the plan will be withdrawn. The timing and amount of an accrual is

dependent upon the type of benefits granted, the timing of communication and other provisions that may be provided in the benefit

plan.

If property, plant and equipment become impaired as a result of the Company’s restructuring efforts, these assets are written down to

their fair value less costs to sell, as the Company commits to dispose of them, and they are no longer in use. Depreciation is

accelerated on property, plant and equipment for the period of time the asset continues to be used until the asset ceases to be used.

For facility closures, we also generally expect to record costs for equipment and inventory relocation, facility carrying costs and costs

to terminate a lease or contract before the end of its term.

Identifying and calculating the cost to exit operations requires certain assumptions to be made, the most significant of which are

anticipated future liabilities, including severance costs, contractual obligations, and the adjustments of property, plant and equipment

and lease ROU assets to their fair value. Our estimates are reasonable, considering our knowledge of the industry we operate in,

previous experience in exiting activities and valuations we may obtain from independent third parties.

1.6. New Accounting Standards Recently Adopted

During the six months ended June 30, 2025, there were no newly issued or newly applicable accounting pronouncements adopted that

had, or are expected to have, a material impact on the Condensed Consolidated Financial Statements.

1.7. New Accounting Standards Not Yet Adopted

In December 2023, the FASB issued ASU 2023-09, “Income Taxes (Topic 740): Improvements to Income Tax Disclosures.” This

ASU requires the annual financial statements to include consistent categories and greater disaggregation of information in the rate

reconciliation, and income taxes paid disaggregated by jurisdiction. ASU 2023-09 is effective for the Company’s annual reporting

periods beginning after December 15, 2024. Adoption is either with a prospective method or a retrospective method of transition.

Early adoption is permitted. The new disclosures (as required) will be included in the consolidated financial statements included in the

Company’s Annual Report on Form 10-K for the year ended December 31, 2025.

In November 2024, the FASB issued ASU 2024-03, “Income Statement - Reporting Comprehensive Income - Expense Disaggregation

Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses” (“ASU 2024-03”). This ASU requires new financial

statement disclosures disaggregating prescribed expense categories within relevant income statement expense captions. ASU 2024-03

will be effective for fiscal years beginning after December 15, 2026, and interim periods beginning after December 15, 2027.

Adoption is either with a prospective method or a retrospective method of transition. Early adoption is permitted. The Company is

currently evaluating the impact of this standard on its disclosures in the consolidated financial statements.