Summary of Significant Accounting Policies	6 Months Ended
Jun. 30, 2026
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed consolidated financial statements and notes have been prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”) for interim financial information and do not contain all of the information and footnotes required by U.S. GAAP for complete financial statements. As such, these unaudited condensed consolidated interim financial statements should be read in conjunction with the audited consolidated financial statements of Ategrity Specialty Insurance Company Holdings and its subsidiaries for the year ended December 31, 2025. The condensed consolidated balance sheet as of December 31, 2025 was derived from the Company’s audited annual consolidated financial statements. In the opinion of management, all adjustments necessary for a fair presentation of the condensed consolidated financial statements have been included. Such adjustments consist only of normal recurring items. All significant intercompany balances and transactions have been eliminated in consolidation. Interim results are not necessarily indicative of results of operations for the full year. Principles of Consolidation The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its consolidated subsidiaries, as well as the Utility Limited Partnership, a variable interest entity (“VIE”) that meets the requirements for consolidation (see Note 3 for further details) (collectively referred to as the “Company”). All significant intercompany balances and transactions have been eliminated in consolidation. Reclassifications and Statement of Cash Flows Presentation Certain prior period amounts have been reclassified to conform to the current period’s presentation. Beginning in the first quarter of 2026, the Company refined the presentation of certain investment-related cash flows within investing activities in the condensed consolidated statements of cash flows. Prior period amounts have been reclassified to conform to the current-period presentation. The reclassification had no impact on net cash provided by operating activities, net cash used in investing activities, net cash provided by financing activities, net change in cash and cash equivalents, net income, total assets, total liabilities or total stockholders’ equity. Reverse Stock Split and Corporate Conversion On June 10, 2025, in connection with its initial public offering, the Company completed its corporate conversion from a Delaware limited liability company to a Nevada corporation and effected a 1-for-10.66 reverse stock split of its outstanding member units. The Corporate Conversion was accounted for as a recapitalization. All common share and per-share amounts presented for prior periods have been retroactively adjusted to reflect the Corporate Conversion and Reverse Stock Split. Estimates and Assumptions The preparation of the condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying disclosures. Management makes estimates and assumptions that include, but are not limited to, reserves for unpaid losses and loss adjustment expenses, fair value of financial assets and liabilities, allowance for credit losses, and income taxes. Those estimates are inherently subject to change, and actual results may ultimately differ from those estimates. Recent Accounting Pronouncements The Company currently qualifies as an “emerging growth company” under the Jumpstart Our Business Startups Act of 2012, or the JOBS Act. Accordingly, the Company is provided the option to adopt new or revised accounting guidance either: (i) within the same periods as those otherwise applicable to non-emerging growth companies; or (ii) within the same time periods as private companies. Accounting Standard Updates Recently Adopted The Company has not adopted any new accounting standards during the three and six months ended June 30, 2026. Accounting Standard Updates Not Yet Adopted In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income -Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, requiring public entities to disclose additional information about specific expense categories in the notes to the financial statements on an interim and annual basis. The guidance is effective for annual reporting periods beginning after December 15, 2026, and for interim reporting periods within annual reporting periods beginning after December 15, 2027, with early adoption permitted. The Company is evaluating the effect of the guidance on its consolidated financial statements and disclosures. In September 2025, the FASB issued ASU 2025-06, Targeted Improvements to the Accounting for Internal-Use Software (Subtopic 350-40). The standard eliminates the previous stage-based model for capitalization, introduces a “probable-to-complete” threshold that defers capitalization if significant development uncertainty exists, and aligns disclosure requirements with those for software developed for external use, as described in ASC 360-10, Property, Plant and Equipment. The ASU also supersedes ASC 350-50, Website Development Costs, unifying all internally developed technology, whether labeled “software” or “website”, under a single framework. The guidance is effective for fiscal years beginning after December 15, 2027, and interim periods within those years, with early adoption permitted. The Company is currently assessing the potential impact of the guidance on its consolidated financial statements and disclosures.

The accompanying unaudited condensed consolidated financial statements and notes have been prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”) for interim financial information and do not contain all of the information and footnotes required by U.S. GAAP for complete financial statements. As such, these unaudited condensed consolidated interim financial statements should be read in conjunction with the audited consolidated financial statements of Ategrity Specialty Insurance Company Holdings and its subsidiaries for the year ended December 31, 2025. The condensed consolidated balance sheet as of December 31, 2025 was derived from the Company’s audited annual consolidated financial statements. In the opinion of management, all adjustments necessary for a fair presentation of the condensed consolidated financial statements have been included. Such adjustments consist only of normal recurring items. All significant intercompany balances and transactions have been eliminated in consolidation. Interim results are not necessarily indicative of results of operations for the full year.

The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its consolidated subsidiaries, as well as the Utility Limited Partnership, a variable interest entity (“VIE”) that meets the requirements for consolidation (see Note 3 for further details) (collectively referred to as the “Company”). All significant intercompany balances and transactions have been eliminated in consolidation.

Certain prior period amounts have been reclassified to conform to the current period’s presentation. Beginning in the first quarter of 2026, the Company refined the presentation of certain investment-related cash flows within investing activities in the condensed consolidated statements of cash flows. Prior period amounts have been reclassified to conform to the current-period presentation. The reclassification had no impact on net cash provided by operating activities, net cash used in investing activities, net cash provided by financing activities, net change in cash and cash equivalents, net income, total assets, total liabilities or total stockholders’ equity.

On June 10, 2025, in connection with its initial public offering, the Company completed its corporate conversion from a Delaware limited liability company to a Nevada corporation and effected a 1-for-10.66 reverse stock split of its outstanding member units. The Corporate Conversion was accounted for as a recapitalization. All common share and per-share amounts presented for prior periods have been retroactively adjusted to reflect the Corporate Conversion and Reverse Stock Split.

The preparation of the condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying disclosures. Management makes estimates and assumptions that include, but are not limited to, reserves for unpaid losses and loss adjustment expenses, fair value of financial assets and liabilities, allowance for credit losses, and income taxes.

The Company currently qualifies as an “emerging growth company” under the Jumpstart Our Business Startups Act of 2012, or the JOBS Act. Accordingly, the Company is provided the option to adopt new or revised accounting guidance either: (i) within the same periods as those otherwise applicable to non-emerging growth companies; or (ii) within the same time periods as private companies.

In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income -Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, requiring public entities to disclose additional information about specific expense categories in the notes to the financial statements on an interim and annual basis. The guidance is effective for annual reporting periods beginning after December 15, 2026, and for interim reporting periods within annual reporting periods beginning after December 15, 2027, with early adoption permitted. The Company is evaluating the effect of the guidance on its consolidated financial statements and disclosures.

In September 2025, the FASB issued ASU 2025-06, Targeted Improvements to the Accounting for Internal-Use Software (Subtopic 350-40). The standard eliminates the previous stage-based model for capitalization, introduces a “probable-to-complete” threshold that defers capitalization if significant development uncertainty exists, and aligns disclosure requirements with those for software developed for external use, as described in

ASC 360-10, Property, Plant and Equipment. The ASU also supersedes ASC 350-50, Website Development Costs, unifying all internally developed technology, whether labeled “software” or “website”, under a single framework. The guidance is effective for fiscal years beginning after December 15, 2027, and interim periods within those years, with early adoption permitted. The Company is currently assessing the potential impact of the guidance on its consolidated financial statements and disclosures.