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STATES\n\nSECURITIES AND EXCHANGE COMMISSION\n\nWashington, D.C. 20549\n\n \n\nFORM 10-Q\n\n \n\n(Mark One)\n\nþ\n\nQUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934\n\nFor the quarterly period ended April 3, 2026\n\nor \n\noTRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934\n\nFor the transition period from to             \n\nCommission File Number: 001-42176\n\n \n\nAmentum Holdings, Inc.\n\n(Exact name of registrant as specified in its charter)\n\n \n\nDelaware99-0622272\n\n(State or other jurisdiction of(I.R.S. Employer\n\nincorporation or organization)Identification No.)\n\n4800 Westfields Blvd., Suite #400\n\nChantilly, Virginia 20151\n\n(Address of principal executive offices)\n\n(703) 579-0410\n\n(Registrant’s telephone number, including area code)\n\n     \n\nSecurities registered pursuant to Section 12(b) of the Act:\n\nTitle of each classTrading Symbol(s)Name of each exchange on which registered\n\nCommon Stock, par value $0.01 per shareAMTMNew York Stock Exchange\n\nIndicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 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 days. Yes þ  No o \n\nIndicate 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). Yes þ  No o\n\nIndicate by check mark whether the Registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.\n\nLarge accelerated filerþAccelerated filero\n\nNon-accelerated fileroSmaller reporting companyo\n\nEmerging growth companyo\n\nIf 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 revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o\n\nIndicate by check mark whether the Registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes o No þ\n\nAs of May 8, 2026, there were 244,316,319 shares outstanding of Amentum Holdings, Inc. common stock, par value of $0.01 per share.\n\nAMENTUM HOLDINGS, INC.\n\n[PART I:](#i3addb113e8154ac8bc0c96c9a5364b8f_13)\n\n[FINANCIAL INFORMATION](#i3addb113e8154ac8bc0c96c9a5364b8f_13)\n\n[Item 1.](#i3addb113e8154ac8bc0c96c9a5364b8f_16)\n\n[Financial Statements (Unaudited)](#i3addb113e8154ac8bc0c96c9a5364b8f_16)\n\n[4](#i3addb113e8154ac8bc0c96c9a5364b8f_16)\n\n[Condensed Consolidated Balance Sheets](#i3addb113e8154ac8bc0c96c9a5364b8f_19)\n\n[4](#i3addb113e8154ac8bc0c96c9a5364b8f_19)\n\n[Condensed Consolidated Statements of Operations](#i3addb113e8154ac8bc0c96c9a5364b8f_22)\n\n[5](#i3addb113e8154ac8bc0c96c9a5364b8f_22)\n\n[Condensed Consolidated Statements of Comprehensive Income](#i3addb113e8154ac8bc0c96c9a5364b8f_25)\n\n[6](#i3addb113e8154ac8bc0c96c9a5364b8f_25)\n\n[Condensed Consolidated Statements of Shareholders' Equity](#i3addb113e8154ac8bc0c96c9a5364b8f_28)\n\n[7](#i3addb113e8154ac8bc0c96c9a5364b8f_28)\n\n[Condensed Consolidated Statements of Cash Flows](#i3addb113e8154ac8bc0c96c9a5364b8f_31)\n\n[8](#i3addb113e8154ac8bc0c96c9a5364b8f_31)\n\n[Notes to Condensed Consolidated Financial Statements](#i3addb113e8154ac8bc0c96c9a5364b8f_34)\n\n[9](#i3addb113e8154ac8bc0c96c9a5364b8f_34)\n\n[Note 1 — Basis of Presentation](#i3addb113e8154ac8bc0c96c9a5364b8f_37)\n\n[9](#i3addb113e8154ac8bc0c96c9a5364b8f_37)\n\n[Note 2 — Recent Accounting Pronouncements](#i3addb113e8154ac8bc0c96c9a5364b8f_40)\n\n[9](#i3addb113e8154ac8bc0c96c9a5364b8f_40)\n\n[Note 3 — Revenues](#i3addb113e8154ac8bc0c96c9a5364b8f_46)\n\n[9](#i3addb113e8154ac8bc0c96c9a5364b8f_46)\n\n[Note 4 — Contract Balances](#i3addb113e8154ac8bc0c96c9a5364b8f_52)\n\n[11](#i3addb113e8154ac8bc0c96c9a5364b8f_52)\n\n[Note 5 — Sales of Receivables](#i3addb113e8154ac8bc0c96c9a5364b8f_55)\n\n[12](#i3addb113e8154ac8bc0c96c9a5364b8f_55)\n\n[Note 6 — Goodwill and Intangible Assets](#i3addb113e8154ac8bc0c96c9a5364b8f_58)\n\n[12](#i3addb113e8154ac8bc0c96c9a5364b8f_58)\n\n[Note 7 — Income Taxes](#i3addb113e8154ac8bc0c96c9a5364b8f_61)\n\n[13](#i3addb113e8154ac8bc0c96c9a5364b8f_61)\n\n[Note 8 — Debt](#i3addb113e8154ac8bc0c96c9a5364b8f_64)\n\n[13](#i3addb113e8154ac8bc0c96c9a5364b8f_64)\n\n[Note 9 — Joint Ventures](#i3addb113e8154ac8bc0c96c9a5364b8f_67)\n\n[14](#i3addb113e8154ac8bc0c96c9a5364b8f_67)\n\n[Note 10 — Accumulated Other Comprehensive Income (Loss)](#i3addb113e8154ac8bc0c96c9a5364b8f_70)\n\n[15](#i3addb113e8154ac8bc0c96c9a5364b8f_70)\n\n[Note 11 — Segment Information](#i3addb113e8154ac8bc0c96c9a5364b8f_73)\n\n[16](#i3addb113e8154ac8bc0c96c9a5364b8f_73)\n\n[Note 12 — Earnings Per Share](#i3addb113e8154ac8bc0c96c9a5364b8f_76)\n\n[17](#i3addb113e8154ac8bc0c96c9a5364b8f_76)\n\n[Note 13 — Legal Proceedings and Commitments and Contingencies](#i3addb113e8154ac8bc0c96c9a5364b8f_79)\n\n[17](#i3addb113e8154ac8bc0c96c9a5364b8f_79)\n\n[Note 14 — Subsequent Events](#i3addb113e8154ac8bc0c96c9a5364b8f_2199023256407)\n\n[18](#i3addb113e8154ac8bc0c96c9a5364b8f_2199023256407)\n\n[Item 2.](#i3addb113e8154ac8bc0c96c9a5364b8f_82)\n\n[Management’s Discussion and Analysis of Financial Condition and Results of Operations](#i3addb113e8154ac8bc0c96c9a5364b8f_82)\n\n[18](#i3addb113e8154ac8bc0c96c9a5364b8f_82)\n\n[Item 3.](#i3addb113e8154ac8bc0c96c9a5364b8f_130)\n\n[Quantitative and Qualitative Disclosures About Market Risk](#i3addb113e8154ac8bc0c96c9a5364b8f_130)\n\n[24](#i3addb113e8154ac8bc0c96c9a5364b8f_130)\n\n[Item 4.](#i3addb113e8154ac8bc0c96c9a5364b8f_133)\n\n[Controls and Procedures](#i3addb113e8154ac8bc0c96c9a5364b8f_133)\n\n[24](#i3addb113e8154ac8bc0c96c9a5364b8f_133)\n\n[PART II:](#i3addb113e8154ac8bc0c96c9a5364b8f_136)\n\n[OTHER INFORMATION](#i3addb113e8154ac8bc0c96c9a5364b8f_136)\n\n[25](#i3addb113e8154ac8bc0c96c9a5364b8f_136)\n\n[Item 1.](#i3addb113e8154ac8bc0c96c9a5364b8f_139)\n\n[Legal Proceedings](#i3addb113e8154ac8bc0c96c9a5364b8f_139)\n\n[25](#i3addb113e8154ac8bc0c96c9a5364b8f_139)\n\n[Item 1A.](#i3addb113e8154ac8bc0c96c9a5364b8f_142)\n\n[Risk Factors](#i3addb113e8154ac8bc0c96c9a5364b8f_142)\n\n[25](#i3addb113e8154ac8bc0c96c9a5364b8f_142)\n\n[Item 2.](#i3addb113e8154ac8bc0c96c9a5364b8f_145)\n\n[Unregistered Sales of Equity Securities and Use of Proceeds](#i3addb113e8154ac8bc0c96c9a5364b8f_145)\n\n[25](#i3addb113e8154ac8bc0c96c9a5364b8f_145)\n\n[Item 3.](#i3addb113e8154ac8bc0c96c9a5364b8f_148)\n\n[Defaults Upon Senior Securities](#i3addb113e8154ac8bc0c96c9a5364b8f_148)\n\n[25](#i3addb113e8154ac8bc0c96c9a5364b8f_148)\n\n[Item 4.](#i3addb113e8154ac8bc0c96c9a5364b8f_151)\n\n[Mine Safety Disclosures](#i3addb113e8154ac8bc0c96c9a5364b8f_151)\n\n[25](#i3addb113e8154ac8bc0c96c9a5364b8f_151)\n\n[Item 5.](#i3addb113e8154ac8bc0c96c9a5364b8f_154)\n\n[Other Information](#i3addb113e8154ac8bc0c96c9a5364b8f_154)\n\n[25](#i3addb113e8154ac8bc0c96c9a5364b8f_154)\n\n[Item 6.](#i3addb113e8154ac8bc0c96c9a5364b8f_157)\n\n[Exhibits](#i3addb113e8154ac8bc0c96c9a5364b8f_157)\n\n[25](#i3addb113e8154ac8bc0c96c9a5364b8f_157)\n\n[Signatures](#i3addb113e8154ac8bc0c96c9a5364b8f_160)\n\n[26](#i3addb113e8154ac8bc0c96c9a5364b8f_160)\n\n3\n\nPART I\n\nFINANCIAL INFORMATION"}