Immunocore Holdings plc

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the shareholders and the Board of Directors of Immunocore Holdings plc

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheet of Immunocore Holdings plc and subsidiaries (the “Company”) as of December 31, 2023, the related consolidated statements of operations and comprehensive loss, shareholders’ equity, and cash flows, for the year ended December 31, 2023, and the related notes (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2023, and the results of its operations and its cash flows for the year ended December 31, 2023, in conformity with accounting principles generally accepted in the United States of America.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company’s internal control over financial reporting as of December 31, 2023, based on criteria established in Internal Control — Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission and our report dated February 28, 2024, expressed an unqualified opinion on the Company’s internal control over financial reporting.

Change in Reporting Framework

As discussed in Note 1 to the financial statements, the Company has changed its reporting framework from International Financial Reporting Standards as issued by the International Accounting Standards Board to accounting principles generally accepted in the United States of America.

These financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits. We are a public accounting firm registered with the 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 audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the 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 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 financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current-period audit of the financial statements that was communicated or required to be communicated to the audit committee and that (1) relates to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the 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.

Product revenue, net – Deductions for government rebates — Refer to Notes 2 and 3 to the financial statements

Critical Audit Matter Description

As more fully disclosed in the Significant Accounting Policies note to the financial statements, the Company recognizes revenue for product sales at the net sales price, which includes deductions for which reserves are established. These deductions include rebates, chargebacks, levies, other customer fees and product returns.

Government rebates are provided to Medicare, state Medicaid programs and similar programs in Europe. Management is required to make significant assumptions and judgments to estimate the government rebate claims related to sales in the respective geographies. These assumptions and judgements include:

These estimates include consideration of internal forecasts of the patient and distributor mix, information obtained from historic claims received and other industry data, and external health coverage statistics.

We identified the deductions for government rebates as a critical audit matter given the complexity involved in determining the significant assumptions and judgments used in estimating the anticipated government rebate claims, which in turn led to a high degree of auditor professional judgment and increased extent of audit effort in auditing such estimates.

How the Critical Audit Matter Was Addressed in the Audit

Our audit procedures related to the government rebates, included the following, among others:

• We tested the effectiveness ofcontrols over management’s processes to account for the deductions associated with government rebates, including controls over determining the underlying assumptions and key inputs into the Company’s process to calculate government rebate adjustment.

• We inspected contractual documents and communications to government agencies and third party advisors associated with the government rebates, and evaluated the consistency of the estimation methodology with the Company’s obligations under such contractual documents and communications.

• We tested the mathematical accuracy of the Company’s calculation of the estimates for government rebates.

• We evaluated whether the accounting treatment for the anticipated government rebate claims is consistent with the relevant accounting standard, ASC 606 Revenue Recognition.

• We performed the following procedures to evaluate the significant assumptions and judgments used by management to estimate the government rebate claims:

/s/Deloitte LLP

Cambridge, United Kingdom

February 28, 2024

We have served as the Company’s auditor since 2023.

Report of Independent Registered Public Accounting Firm

To the Shareholders and Board of Directors

Immunocore Holdings plc

Opinion on the Consolidated Financial Statements

We have audited the accompanying Consolidated Balance Sheet of Immunocore Holdings plc and subsidiaries (the Company) as of December 31, 2022, the related Consolidated Statements of Operations and Comprehensive Loss, shareholders’ equity, and cash flows for each of the years in the two year period ended December 31, 2022, and the related notes (collectively, the consolidated financial statements). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2022, and the results of its operations and its cash flows for each of the years in the two year period ended December 31, 2022, in conformity with U.S. generally accepted accounting principles.

These consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on these consolidated financial statements 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 audit to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud. Our audits 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. We believe that our audits provides a reasonable basis for our opinion.

/s/ KPMG LLP

We served as the Company’s auditor from 2009 to 2023

London, United Kingdom

February 28, 2024