PACKAGING CORP OF AMERICA

PCA maintains disclosure controls and procedures (as defined in Rule 13a-15(e) of the Securities Exchange Act of 1934) that are designed to provide reasonable assurance that information required to be disclosed in PCA’s filings under the Securities Exchange Act is recorded, processed, summarized and reported within the periods specified in the rules and forms of the SEC and that such information is accumulated and communicated to PCA’s management, including its Chief Executive Officer and Chief Financial Officer, as appropriate, to allow timely decisions regarding required disclosure.

Prior to filing this report, PCA completed an evaluation under the supervision and with the participation of PCA’s management, including PCA’s Chief Executive Officer and Chief Financial Officer, of the effectiveness of the design and operation of PCA’s disclosure controls and procedures as of March 31, 2024. The evaluation of PCA’s disclosure controls and procedures included a review of the controls’ objectives and design, PCA’s implementation of the controls, and the effect of the controls on the information generated for use in this report. Based on this evaluation, PCA’s Chief Executive Officer and Chief Financial Officer concluded that PCA’s disclosure controls and procedures were effective at the reasonable assurance level as of March 31, 2024.

Changes in Internal Control over Financial Reporting

There have been no changes in our internal control over financial reporting (as defined in Rule13a-15(f) under the Exchange Act) that occurred during the most recent fiscal quarter ended March 31, 2024 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

PART II

OTHER INFORMATION