Basis of consolidation

The accompanying consolidated financial statements include the Company’s accounts and the accounts of the Company’s wholly-owned subsidiaries. All material intercompany accounts and transactions have been eliminated in consolidation.

The Company’s fiscal year ends on December 31. References to fiscal 2025, for example, refer to the fiscal year ended December 31, 2025.

Recent Accounting Pronouncements Adopted

ASU 2023-09, Income Taxes (Topic 740)

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. ASU 2023-09 requires all entities to provide more transparency about income tax information through improvements to income tax disclosures primarily related to the rate reconciliation and income taxes paid information. The amendments in this Update also eliminate requirements such as (1) the disclosure of the nature and estimate of the range of the reasonably possible change in the unrecognized tax benefits balance in the next 12 months, (2) or making a statement that an estimate of the range cannot be made, and (3) the disclosure of the cumulative amount of each type of temporary difference when a deferred tax liability is not recognized because of the exceptions to comprehensive recognition of deferred taxes related to subsidiaries and corporate joint ventures. Lastly, the amendments in this Update replace the term ‘public entity’ as currently used in Topic 740 with the term ‘public business entity’. ASU 2023-09 is effective for the Company’s fiscal years beginning after December 15, 2024. The Company adopted ASU 2023-09 in the fourth quarter of fiscal 2025 on a retrospective basis. The adoption of ASU 2023-09 did not have a significant impact to the Company's financial statements.

ASU 2025-05, Financial Instruments - Credit Losses (Topic 326)

In July 2025, the FASB issued ASU 2025-05, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses for Accounts Receivable and Contract Assets. The amendments in this update provides a practical expedient for measuring expected credit losses on current trade receivables and contract assets by assuming that current conditions remain unchanged over the life of the asset. ASU 2025-05 is effective for the Company's fiscal years beginning after December 15, 2025, and interim periods with those annual reporting periods. The Company adopted ASU 2025-05 in the fourth quarter of fiscal 2025. The adoption of ASU 2025-05 did not have a significant impact to the Company's consolidated financial statements.

Recent Accounting Pronouncements Not Yet Adopted

ASU 2024-03, Disaggregation of Income Statement Expenses (Topic 220)

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. The new guidance is intended to provide investors more detailed disclosures around certain types of expenses, including employee compensation, depreciation, intangible asset amortization, and other specific expense categories. This standard also requires disclosure of the total amount of selling expenses to be presented in the notes to the financial statements. ASU 2024-03 is effective for the Company's fiscal years beginning after December 15, 2026, and interim periods within fiscal years after December 15, 2027. The Company is currently assessing the impact this standard will have on the Company's consolidated financial statements but does not expect it to have a material impact on the consolidated financial statements.

ASU 2024-04, Induced Conversions of Convertible Debt Instruments (Subtopic 470)

In November 2024, the FASB issued ASU 2024-04, Debt - Debt with Conversion and Other Options (Subtopic 470-20): Induced Conversions of Convertible Debt Instruments Disclosures. The amendments in this Update is intended to improve relevance and consistency in application of the induced conversion guidance in Subtopic 470-20. Additionally, the purpose of the Update is to clarify the requirements for determining whether certain settlements of convertible debt instruments should be accounted for as induced conversion. Under the amendments, to account for a settlement of a convertible debt instrument as an induced conversion, an inducement offer is required to provide the debt holder with, at a minimum, the consideration (in form and amount) issuable under the conversion privileges provided in the terms of the instrument. ASU 2024-04 is effective for the Company's fiscal years beginning after December 15, 2025, and interim periods with those annual reporting periods. The Company is currently assessing the impact this standard will have on the Company's consolidated financial statements but does not expect it to have a material impact on the consolidated financial statements.

ASU 2025-06, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40)

In September 2025, the FASB issued ASU 2025-06, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software. The amendments in this Update remove all references to prescriptive and sequential software developmental stages (referred to as "project stages"). ASU 2025-06 requires entities to begin capitalizing software costs when management authorizes and commits to funding the software project, and it is probable that the project will be completed and the software will be used for its intended purpose. ASU 2025-06 is effective for the Company's fiscal years beginning after December 15, 2027, and interim periods with those annual reporting periods. Early adoption is permitted. The Company is currently assessing the impact this standard will have on the Company's consolidated financial statements.

ASU 2025-11, Interim Reporting (Topic 270): Narrow-Scope Improvements

In November 2025, the FASB issued ASU 2025-11, Interim Reporting (Topic 270): Narrow-Scope Improvements to improve the navigability of required interim disclosures and clarify when applicable. ASU 2025-11 is not intended to change the fundamental nature of interim reporting or expand or reduce current interim disclosure requirements, but to provide clarity on current interim reporting requirements. ASU 2025-11 is effective for the Company's fiscal years beginning after December 15, 2027, and interim

periods with those annual reporting periods. Early adoption is permitted. The Company is currently assessing the impact this standard will have on the Company's condensed consolidated financial statements.

ASU 2025-12, Codification Improvements

In December 2025, the FASB issued ASU 2025-12, Codification Improvements to address suggestions received from stakeholders on the Accounting Standards Codification and to make other incremental improvements to U.S. GAAP. The update represents changes to the Codification that (1) clarify, (2) correct errors, and (3) make minor improvements. ASU 2025-12 is effective for the Company's fiscal years beginning after December 15, 2026, and interim periods with those annual reporting periods. The Company is currently assessing the impact this standard will have on the Company's consolidated financial statements.

Cash and cash equivalents

The Company considers all highly liquid investments with original maturities of three months or less from the date of purchase to be cash equivalents. Cash equivalents consist of money market funds and marketable securities and are stated at fair value.

Marketable securities

All marketable securities have been classified as available-for-sale and are carried at estimated fair value. The Company determines the appropriate classification of investments in debt securities at the time of purchase. Securities may have stated maturities greater than one year. All marketable securities are considered available to support current operations and are classified as current assets.

For available-for-sale debt securities in an unrealized loss position, management first assesses whether it intends to sell, or it is more likely than not that it will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value and recognized in other income (expense) in the results of operations. For available-for-sale debt securities that do not meet the aforementioned criteria, management evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, management considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, an allowance is recorded for the difference between the present value of cash flows expected to be collected and the amortized

cost basis of the security. Impairment losses attributable to credit loss factors are charged against the allowance when management believes an available-for-sale security is uncollectible or when either of the criteria regarding intent or requirement to sell is met.

Any unrealized losses from declines in fair value below the amortized cost basis as a result of non-credit loss factors is recognized as a component of accumulated other comprehensive loss. Realized gains and losses and declines in fair value, if any, on available-for-sale securities are included in other income (expense) in the results of operations. The cost of securities sold is based on the specific-identification method.

Accounts receivable

Accounts receivable are stated at net realizable value and include both billed and unbilled receivables. Accounts receivable are net of an allowance for credit losses, are not collateralized, and do not bear interest. Payment terms range from due immediately to due within 90 days. Unbilled receivable balances arise primarily when the Company provides services in advance of invoicing for those services. Billing for revenues relating to the volume of transactions processed by the customer are generally billed a month in arrears, resulting in an unbilled receivable. The accounts receivable balance at December 31, 2025 and December 31, 2024 included unbilled receivables of $14.3 million, and $15.5 million, respectively.

Identified risks pertaining to the Company’s invoiced accounts receivable include the delinquency level and customer type. The estimate of the amount of accounts receivable that may not be collected is based on aging of the accounts receivable balances, historical customer delinquency, and assessment of the overall portfolio.

Deferred commissions

The Company capitalizes certain sales commissions earned by the Company's sales and account management teams as these commission payments are considered incremental and recoverable costs of obtaining a contract with a customer. The Company begins amortizing deferred commissions costs for a particular customer agreement once the revenue recognition criteria are met and amortizes those deferred costs over the expected period of customer benefit. The Company amortizes deferred sales commissions ratably over the customer life which is approximately 3 years. The amortization of deferred commission is recorded in sales and marketing expense within the consolidated statement of operations. The Company periodically reviews the carrying amount of deferred commissions to determine whether events or changes in circumstances have occurred that could impact the period of benefit of the deferred costs.

Capitalized Internal-Use Software Costs

The Company capitalizes software costs associated with the development of internal software in accordance with ASC 350-40, Intangibles - Goodwill and Other - Internal-Use Software. These costs are incurred during the application development phase and meet other requirements for capitalization. Capitalized software costs are recorded as part of property and equipment, net, and capitalized software costs related to hosting arrangements are recorded within prepaid expenses and other assets within the condensed consolidated balance sheets. These costs are amortized once placed in service over the useful life, which is generally 36 months.

The Company's unamortized capitalized software costs recorded as part of property and equipment, net was $9.1 million and $6.2 million as of December 31, 2025 and 2024, respectively. The Company recorded capitalized software cost amortization expense of $2.5 million, $1.7 million, and $1.1 million for the years ended December 31, 2025, 2024, and 2023, respectively.

Of the total unamortized capitalized software costs, recorded in prepaid expenses and other assets, net, as of December 31, 2025, $8.4 million relate to capitalized implementation costs of hosting arrangements that are service contracts. The related amortization expense recorded was $1.0 million for the year ended December 31, 2025. No amortization expense was recorded for the years ended December 31, 2024 and 2023.

There was no impairment of capitalized software costs for the year ended December 31, 2025.

The Company determines if an arrangement is a lease or contains a lease at inception. At the commencement date of a lease, the Company recognizes a liability to make lease payments and an asset representing the right to use the underlying asset during the lease term. The lease liability is measured at the present value of lease payments over the lease term. As the Company's leases typically do not provide an implicit rate, the Company uses its incremental borrowing rate for most leases. The right-of-use (“ROU”) asset is measured at cost, which includes the initial measurement of the lease liability and initial direct costs incurred and excludes lease incentives. The Company assesses leases for impairment on an annual basis or as needed when events or circumstances necessitate.

Lease terms may include options to extend or terminate the lease. The Company records a ROU asset and a lease liability when it is reasonably certain that the Company will exercise that option. Operating lease costs are recognized on a straight-line basis over the lease term.

The Company evaluates intangible assets and other long-lived assets (asset groups) whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable, including, but not limited to, significant adverse changes in business climate, market conditions or other events that indicate an asset's carrying amount may not be recoverable. Recoverability of these assets is measured by comparing the carrying amount of each asset group to the future undiscounted cash flows the asset is expected to generate. If the undiscounted cash flows used in the test for recoverability are less than the carrying amount of these assets, the carrying amount of such assets is reduced to fair value.

The Company assesses goodwill for impairment annually during the fourth quarter, or more frequently if events or changes in circumstances would more likely than not reduce the fair value below its carrying value. When the Company elects to perform a qualitative assessment and conclude it is not more likely than not the fair value is less than its carrying value, no further assessment is necessary; otherwise, a quantitative assessment is performed and the fair value is determined. If the carrying value exceeds the estimated fair value, impairment is recorded.

Revenue Recognition

Subscription solutions

Subscription solutions revenue consists primarily of subscription fees from all plans and recurring professional services. Subscription solutions are typically charged annually for the Company’s customers to sell their products and process transactions on the BigCommerce platform. Subscription solutions are generally charged per online store and are based on the store’s subscription plan. Subscription fees are adjusted if a customer’s gross merchandise volume ("GMV") or orders processed are above specified plan

thresholds on a trailing twelve-month basis. For most subscription solutions arrangements, the Company utilizes the right to invoice practical expedient and, therefore, recognizes fixed monthly fees or a pro-rata portion of fees and any transaction fees as revenue in the month they are earned. The Company utilizes a pricing structure that provides a discount to the contractual price for customers who have prepayment terms. The total subscription fee and recurring professional services are recognized on a straight-line basis over the term of the contract. In determining the amount of revenue to be recognized, the Company determines whether collection of the entire transaction price is probable. Only amounts deemed probable are recognized as revenue. Key factors in this determination are historical contract termination rates, general economic factors, and customer specific factors.

Subscription solutions includes revenue from Feedonomics. Feedonomics provides an AI-based product data feed management platform and related services that enables online retailers and other sellers to automate online listings of the sellers’ information across multiple third-party marketplaces and advertisers. The Company provides these services under service contracts which are generally one year or less, and in many cases month-to-month. These service types may be sold stand-alone or as part of a multi-service bundle (e.g. both marketplaces and advertising). Services are performed and fees are determined based on monthly usage and are billed in arrears.

Contracts with the Company’s retail customers are generally month-to-month, while contract terms with the Company’s enterprise customers generally range from one to three years. Contracts are typically non-cancelable and do not contain refund-type provisions. Revenue is presented net of sales tax and other taxes the Company collects on behalf of governmental authorities.

Partner and services

The Company's partner and services revenue includes revenue share, partner technology integrations, professional services, and marketing services provided to partners. Revenue share primarily relates to fees earned by the Company’s partners from customers using the BigCommerce platform, where the Company has an arrangement with such partners to share such fees as they occur. Revenue share is recognized at the time the earning activity is complete, which is generally monthly and variable based on customer usage. Revenue for partner technology integrations is recorded on a straight-line basis over the life of the contract commencing when the integration has been completed. Revenue for marketing services are recognized either at the time the earning activity is complete, or ratably over the length of the contract, depending on the nature of the obligations in the contract. Payments received in advance of services being rendered are recorded as deferred revenue and recognized when the obligation is completed.

Professional services, which primarily consist of education packages, launch services, solutions architecting, implementation consulting, and catalog transfer services, are generally billed and recognized as revenue when delivered. The Company also derives revenue from the sales of website themes and applications upon delivery.

The Company recognizes partner revenue share on a net basis as the Company has determined that the Company is the agent in the Company’s arrangements with third-party application providers. All other revenue is recognized on a gross basis, as the Company has determined the Company is the principal in these arrangements.

Contracts with multiple performance obligations

A performance obligation is a promise in a contract to transfer a distinct good or service to the customer. Determining whether products and services are considered distinct performance obligations that should be accounted for separately versus together may require judgment.

The Company’s subscription contracts are generally comprised of a single performance obligation to provide access to the BigCommerce platform, but can include additional performance obligations. For contracts with multiple performance obligations where the contracted price differs from the standalone selling price (“SSP”) for any distinct service, the Company may be required to allocate the contract’s transaction price to each performance obligation using the Company’s best estimate of SSP. Judgment is required to determine the SSP for each distinct performance obligation. A contract’s transaction price is allocated to each distinct performance obligation and recognized as revenue when, or as, the performance obligation is satisfied. The primary method used to estimate SSP is the observable prices of products or services sold or priced separately in comparable circumstances to similar customers.

Contracts with the Company’s partners may include multiple performance obligations, which can include integrations and marketing activities. In determining whether integration services are distinct from hosting services the Company considers various factors. These considerations include the level of integration, interdependency, and interrelation between the implementation and hosting services. The Company has concluded that the integration services included in contracts with hosting obligations are not distinct. As a result, the Company defers any arrangement fees for integration services and recognizes such amounts over the life of the hosting obligation commencing when the integration has been completed. To determine if marketing activities are distinct, the Company considers the nature of the promise in the contract, the timing of payment, and the partner expectations. Additional consideration for some partner contracts varies based on the level of customer activity on the platform. Certain agreements contain minimum guarantees of revenue share. These contracts are evaluated to determine if the guaranteed minimum is substantive. If the

minimum is deemed substantive, revenue is recognized ratably over the life of the agreement. For most contracts, variable fees are recognized in the period they are earned as the Company utilizes the right to invoice practical expedient.

The timing of revenue recognition, billings and cash collections can result in billed accounts receivable, unbilled receivables, contract assets, and deferred revenue.

Remaining performance obligation

The Company's remaining performance obligations are contracted revenue minimums that have not yet been recognized, including amounts that will be invoiced and recognized as revenue in future periods. Remaining performance obligation is subject to future economic risks, including bankruptcies, regulatory changes and other market factors. The majority of the Company's noncurrent remaining performance obligations are expected to be recognized in the next 13 to 36 months. One of the Company's strategic partner's contract renewal is reflected in the total remaining performance obligation.

Restructuring charges

Costs to restructure certain internal operations are accounted for as one-time termination and exit costs. A liability for a cost associated with restructuring activities is recognized and measured at its estimated fair value in our consolidated balance sheet in the period the liability is incurred. All costs relating to restructurings are recorded as "Restructuring charges" in the consolidated statement of operations.

We recognize employee severance costs when payments are probable and amounts are estimable or when notification occurs depending on whether the severance costs paid are part of an ongoing benefit arrangement. Costs related to contracts without future benefit or contract terminations are recognized at the earlier of the contract termination or the cease-use dates. Additionally, restructuring charges include considerations of various capital alternatives or changes in business activities which include expenses related to retention and relocation benefits, accelerated depreciation, professional services, and other costs.

Stock-based compensation

The Company issues stock options, restricted stock units (“RSUs”) and performance based restricted stock units (“PSUs”) to eligible employees and directors.

The Company values stock options using the Black-Scholes option-pricing model at the date of grant and recognizes the related stock-based compensation expense on a straight-line basis over the service period, net of estimated forfeitures, which is typically four years.

The Company measures the fair value of RSUs based on the closing market price of the common stock on the date of grant. RSUs generally vest over a four-year period either (i) in equal annual installments, or (ii) 25 percent on the one-year anniversary of the grant date with the remaining 75 percent vesting in equal quarterly installments thereafter, in each case, subject to continued service. Stock-based compensation expense is recognized straight-line over the requisite service period.

The Company grants PSUs to executive officers and other members of senior management which provide for shares of common stock to be earned based on the Company's total stockholder return compared to the Russell 2000 index, and are referred to as market-based awards. The Company values these market-based awards on the grant date using the Monte Carlo simulation model. The determination of fair value is affected by the Company's stock price and a number of assumptions including the expected volatility and the risk-free interest rate. The Company assumes no dividend yield and recognizes stock-based compensation expense on a

straight-line basis from grant date over the service period of the award. The market-based awards will cliff-vest at the end of the three-year period ranging from 0 percent to 200 percent of the target number of PSUs granted.

The Company also grants PSUs to executive officers and other members of senior management which provide for shares of common stock to be earned based on its attainment of the Company's adjusted earnings before interest, taxes, depreciation and amortization (“adjusted EBITDA”) and revenue relative to a target specified in the applicable agreement, and are referred to as Company performance-based awards. The Company typically values these awards at the closing market price on the date of grant. The vesting of Company performance-based awards is conditioned upon the achievement of certain targets and will vest in three annual tranches in a percentage of the target number of shares between 0 percent to 200 percent. The Company recognizes stock-based compensation expense on a straight-line basis over the service period, if it is probable that the performance condition will be achieved. Adjustments to stock-based compensation expense are made, as needed, each reporting period based on changes in our estimate of the number of units that are probable of vesting.

Income taxes

The Company accounts for income taxes under the asset and liability method. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax balances are adjusted to reflect tax rates based on currently enacted tax laws, which will be in effect in the years in which the temporary differences are expected to reverse. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in the results of operations in the period of the enactment date. A valuation allowance is recorded to reduce the carrying amounts of deferred tax assets unless it is more likely than not that those assets will be realized. To date, the Company has provided a valuation allowance against all of its deferred tax assets as the Company believes the objective and verifiable evidence of its historical pretax net losses outweighs any positive evidence of its forecasted future results. The Company will continue to monitor the positive and negative evidence, and will adjust the valuation allowance as sufficient objective positive evidence becomes available.

The Company recognizes the tax effects of an uncertain tax position only if it is more likely than not to be sustained based solely upon its technical merits at the balance sheet date. The unrecognized tax benefit is the difference between the tax benefit recognized and the tax benefit claimed on the Company’s income tax return. All of the Company’s gross unrecognized tax benefits, if recognized, would not affect its effective tax rate but would be recorded as an adjustment to equity before consideration of valuation allowances. The Company does not expect unrecognized tax benefits to decrease within the next twelve months. The Company recognizes accrued interest and penalties related to unrecognized tax benefits as a component of income tax expense. As of December 31, 2025, the Company has not accrued any interest or penalties related to unrecognized tax benefits. The Company believes that all material tax positions in the current and prior years have been analyzed and properly accounted for and that the risk of additional material uncertain tax positions that have not been identified is remote.