FORM 10-K ☒ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2025 or NORTHROP GRUMMAN CORPORATION (Exact name of registrant as specified in its charter) (I.R.S. EmployerIdentification Number) (703)280-2900(Registrant’s telephone number, including area code) Securities registered pursuant to section 12(b) of the Act: Securities registered pursuant to Section12(g) of the Act: NoneIndicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes☒No☐ Indicate by check mark if the registrant is not required to file reports pursuant to Section13 or 15(d) of the Act. Yes☐No☒ Indicate 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 such shorter period that the registrant was required to file such reports), and (2)has been subject to such filing requirements for the past 90days. Yes☒No☐ 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). Yes☒No☐ 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 emerging growthcompany. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of theExchange Act: Large Accelerated Filer☒Accelerated Filer☐Smaller Reporting Company☐Non-accelerated Filer☐Emerging Growth Company☐ 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 thecorrection of an error to previously issued financial statements.☐ 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).☐ Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes☐No☒ As of June 30, 2025, the aggregate market value of the common stock (based upon the closing price of the stock on the New York Stock Exchange) of the registrant heldby non-affiliates was approximately $71.5 billion. As of January22, 2026, 141,921,621 shares of common stock were outstanding. DOCUMENTS INCORPORATED BY REFERENCEPortions of Northrop Grumman Corporation’s Proxy Statement to be filed with the Securities and Exchange Commission pursuant to Regulation 14A for the 2026 Annual Meeting of Shareholders are incorporated by reference in Part III of this Form 10-K. NORTHROP GRUMMAN CORPORATIONTABLE OF CONTENTS PART I Item1.BusinessItem1A.Risk FactorsItem1B.Unresolved Staff CommentsItem 1C.CybersecurityItem2.PropertiesItem3.Legal ProceedingsItem4.Mine Safety Disclosures PART II Item5.Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity SecuritiesItem6.[Reserved]Item7.Management’s Discussion and Analysis of Financial Condition and Results of OperationsOverviewConsolidated Operating ResultsSegment Operating ResultsProduct and Service AnalysisBacklogLiquidity and Capital ResourcesCritical Accounting Policies and EstimatesItem7A.Quantitative and Qualitative Disclosures About Market RiskItem8.Financial Statements and Supplementary DataReport of Independent Registered Public Accounting FirmConsolidated Statements of Earnings and Comprehensive IncomeConsolidated Statements of Financial PositionConsolidated Statements of Cash FlowsConsolidated Statements of Changes in Shareholders’ EquityNotes to Consolidated Financial Statements1. Summary of Significant Accounting Policies2. Earnings Per Share, Share Repurchases and Dividends on Common Stock3. Accounts Receivable, Net4. Unbilled Receivables, Net5. Inventoried Costs, Net6. Income Taxes7. Goodwill and Other Purchased Intangible Assets8. Fair Value of Financial Instruments9. Debt10. Investigations, Claims and Litigation