PARSONS CORP

Report of Independent Registered Public Accounting Firm

To the Board of Directors and Shareholders of Parsons Corporation

Opinions on the Financial Statements and Internal Control over Financial Reporting

We have audited the accompanying consolidated balance sheets of Parsons Corporation and its subsidiaries (the “Company”) as of December 31, 2024 and 2023, and the related consolidated statements of income, of comprehensive income, of changes in shareholders’ equity and of cash flows for each of the three years in the period ended December 31, 2024, including the related notes and schedule of valuation and qualifying accounts for each of the three years in the period ended December 31, 2024 appearing under Item 15(a)(2) (collectively referred to as the “consolidated financial statements”). We also have audited the Company's internal control over financial reporting as of December 31, 2024 based on criteria established in Internal Control - Integrated Framework(2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).

In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the financial position of the Company as of December 31, 2024 and 2023, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2024 in conformity with accounting principles generally accepted in the United States of America. Also in our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2024, based on criteria established in Internal Control - Integrated Framework(2013) issued by the COSO.

Change in Accounting Principle

As discussed in Note 2 to the consolidated financial statements, the Company changed the manner in which it accounts for debt with conversion and other options in 2024.

Basis for Opinions

The Company's management is responsible for these consolidated financial statements, for maintaining effective internal control over financial reporting, and for its assessment of the effectiveness of internal control over financial reporting, included in Management’s Annual Report on Internal Control over Financial Reporting appearing under Item 9A. Our responsibility is to express opinions on the Company’s consolidated financial statements and on the Company's internal control over financial reporting based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud, and whether effective internal control over financial reporting was maintained in all material respects.

Our audits of the consolidated financial statements included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. Our audit of internal control over financial reporting included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audits also included performing such other procedures as we considered necessary in the circumstances. We believe that our audits provide a reasonable basis for our opinions.

As described in Management’s Annual Report on Internal Control over Financial Reporting, management has excluded BlackSignal Technologies, LLC (“BlackSignal”) and BCC Engineering, LLC (“BCC”) from its assessment of internal controls over financial reporting as of December 31, 2024, because they were acquired by the Company in purchase business combinations during 2024. We have also excluded BlackSignal and BCC from our audit of internal control over financial reporting. BlackSignal and BCC are wholly-owned subsidiaries whose total assets and total revenues excluded from management’s assessment and our audit of internal control over financial reporting represent approximately 4.3% and 4.8%, of total assets, respectively and approximately 0.3% and 0.3% of total revenues, respectively, of the related consolidated financial statement amounts as of and for the year ended December 31, 2024.

Definition and Limitations of Internal Control over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Critical Audit Matters

The critical audit matter communicated below is a matter arising from the current period audit of the consolidated financial statements that was communicated or required to be communicated to the audit committee and that (i) relates to accounts or disclosures that are material to the consolidated financial statements and (ii) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

Revenue Recognition – Determination of Estimated Contract Cost and Variable Consideration Related to Estimated Claims Revenue for Fixed-Price Contracts Recognized Over Time

As described in Notes 2 and 4 to the consolidated financial statements, revenue is derived from long-term contracts with customers whereby the Company provides planning, design, engineering, technical, and construction and program management services. The Company enters into cost-plus, time-and-materials, and fixed-price contracts with its customers. Fixed-price contract revenue recognized was $2.8 billion for the year ended December 31, 2024, which accounts for approximately 42% of the Company’s consolidated revenue. Fixed-price contract revenue is recognized over time using an input measure (i.e., costs incurred to date relative to total estimated costs at completion) to measure progress. Under the cost-to-cost measure of progress method, the extent of progress towards completion is measured based on the ratio of total costs incurred-to-date to the total estimated costs at completion of the performance obligation. Revenues, including estimated fees or profits, are recorded proportionally as costs are incurred. Management includes variable consideration, such as claims revenue, in the estimated transaction price to the extent it is probable that a significant reversal of cumulative revenue recognized will not occur or when the uncertainty associated with the variable consideration is resolved. Contract costs consist of direct costs on contracts, including labor and materials, amounts payable to subcontractors, direct overhead costs and equipment expense (primarily depreciation, fuel, maintenance and repairs). Changes to estimated contract costs, either due to unexpected events or revisions to management’s initial estimates, for a given project are recognized in the period in which they are determined. Recognition of profit on long-term contracts requires the use of assumptions and estimates related to total contract revenue and in particular estimated claims revenue, total estimated cost at completion, and the measurement of progress towards completion. Management’s estimates are continually evaluated as work progresses and are revised when necessary.

The principal considerations for our determination that performing procedures relating to revenue recognition, specifically the determination of estimated contract cost and variable consideration related to estimated claims revenue for fixed-price contracts recognized over time is a critical audit matter are (i) the significant judgment by management in determining the estimated contract cost and variable consideration related to estimated claims revenue for fixed-price contracts recognized over time; (ii) a high degree of auditor judgment, subjectivity, and effort in performing procedures and evaluating audit evidence for the estimated contract cost and variable consideration related to estimated claims revenue for fixed-price contracts recognized over time.

Addressing the matter involved performing procedures and evaluating audit evidence in connection with forming our overall opinion on the consolidated financial statements. These procedures included testing the effectiveness of controls relating to the revenue recognition process, including controls over the determination of estimated contract cost and variable consideration related to estimated claims revenue for fixed-price contracts recognized over time. These procedures also included, among others, for a selection of fixed-price contracts (i) evaluating and testing management’s process for determining the estimated contract cost and variable consideration related to estimated claims revenue, which included reading contracts and other documents related to the estimates, and testing of underlying incurred and estimated contract costs; (ii) assessing management’s ability to reasonably estimate total contract costs by performing a comparison of the actual estimated contract cost as compared with prior period estimates, including evaluating the timely identification of circumstances that may warrant a modification to the estimated contract cost; and (iii) evaluating estimated claims revenue by inquiry with external legal counsel regarding the underlying claim and agreeing estimated claims revenue to documents related to those estimates.

/s/PricewaterhouseCoopers LLP

Los Angeles, California

February 19, 2025

We have served as the Company’s auditor since at least 1969. We have not been able to determine the specific year we began serving as auditor of the Company.