Indicate by check mark if the registrant is not required to file reports pursuant to Section13 or Section15(d) of the Act.YesNoIndicate by check mark whether the registrant (1)has filed all reports required to be filed by Section13 or 15(d) of the Securities Exchange Act of 1934 during thepreceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T(§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).YesNo Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerginggrowth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revisedfinancial accounting standards provided pursuant to Section 13(a) of the Exchange Act. Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control overfinancial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of theregistrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). Aggregate market value of voting and non-voting common equity held by non-affiliates of the registrant as of June30, 2025 (the last business day of the registrant’smost recently completed second fiscal quarter): $242,702,935* Number of shares of Common Stock outstanding as of March 6, 2026: 34,756,980 *In determining this figure, an aggregate of 7,296,737 shares of Common Stock beneficially owned by John D. Gottwald, William M. Gottwald, James T. Gottwald,and Residual 10-year CLAT UA FDGJR Living Trust and the members of their immediate families has been excluded because the shares are deemed to be held byaffiliates. The aggregate market value has been computed based on the closing price in the New York Stock Exchange on June30, 2025. Documents Incorporated by Reference Part I Item1. BusinessItem1A.Risk FactorsItem1B.Unresolved Staff CommentsItem 1C.CybersecurityItem2.PropertiesItem3.Legal ProceedingsItem4.Mine Safety Disclosures PartII Item5.Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of EquitySecuritiesItem6.[RESERVED]Item7.Management’s Discussion and Analysis of Financial Condition and Results of OperationsItem7A.Quantitative and Qualitative Disclosures About Market RiskItem8.Financial Statements and Supplementary DataItem9.Changes in and Disagreements with Accountants on Accounting and Financial DisclosureItem9A.Controls and ProceduresItem9B.Other InformationItem 9C.Disclosure Regarding Foreign Jurisdictions that Prevent Inspections PartIII Item10.Directors, Executive Officers and Corporate Governance Item11.Executive CompensationItem12.Security Ownership of Certain Beneficial Owners and Management and Related Stockholder MattersItem13.Certain Relationships and Related Transactions, and Director IndependenceItem14.Principal Accountant Fees and Services PartIV Item15.Exhibits and Financial Statement SchedulesItem16.Form 10-K Summary PART I Item 1.BUSINESS Description of Business Tredegar Corporation is engaged, through its subsidiaries, in the manufacture of aluminum extrusions and polyethylene andpolypropylene plastic films. Unless the context requires otherwise, all references herein to “Tredegar,” “the Company,” “we,” “us” or In the fourth quarter of 2025, the Company renamed the segment formerly known as “PE Films.” This segment will be referredto as “High Performance Films” going forward. The product previously known as polyethylene overwrap films was renamed toadvanced packaging films. There were no changes to the operations reported within the High Performance Films segment. The On November 1, 2024, the Company completed the sale of its flexible packaging films business (also referred to as “Terphane”)headquartered in Brazil to Oben Group. All historical results for Terphane have been presented as discontinued operations. For more A