Accounting Policies	3 Months Ended
Mar. 31, 2026
Accounting Policies [Abstract]
Accounting Policies	Accounting Policies Organization James River Group Holdings, Inc. (referred to as “JRG Holdings” or, with its subsidiaries, the “Company”) is a Delaware holding company organized for the purpose of acquiring and managing insurance entities. The Company owns five insurance companies based in the United States (“U.S.”) focused on specialty insurance niches as described below: •James River Group is a Delaware domiciled insurance holding company formed in 2002, which owns all of the Company’s U.S.-based subsidiaries, either directly or indirectly through one of its wholly-owned U.S. subsidiaries. James River Group oversees the Company’s U.S. insurance operations. •James River Insurance Company (“James River Insurance”) is an Ohio domiciled excess and surplus lines insurance company that, with its wholly-owned insurance subsidiary, James River Casualty Company, is authorized to write business in every state and the District of Columbia. •Falls Lake National Insurance Company (“Falls Lake National”) is an Ohio domiciled insurance company which wholly owns Stonewood Insurance Company (“Stonewood Insurance”), an Ohio domiciled company, and Falls Lake Fire and Casualty Company, a California domiciled company. Falls Lake National and its subsidiaries primarily write specialty admitted fronting and program business. The Company previously owned JRG Reinsurance Company Ltd. (“JRG Re”), a Bermuda domiciled reinsurer, which comprised the former Casualty Reinsurance segment, and which, prior to the suspension of its underwriting activities in 2023, primarily provided non-catastrophe casualty reinsurance to U.S. third parties. On November 8, 2023, the Company entered into an agreement to sell JRG Re. The sale closed on April 16, 2024 and resulted in the Company’s disposition of its casualty reinsurance business and related assets. The Company has no continued involvement with JRG Re following the sale. See Discontinued Operations below and Note 2 for additional disclosure. Basis of Presentation The accompanying condensed consolidated financial statements and notes have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and do not contain all of the information and footnotes required by U.S. GAAP for complete financial statements. The condensed consolidated financial statements include the results of the Company and its subsidiaries from their respective dates of inception or acquisition, as applicable. Readers are urged to review the Company’s Annual Report on Form 10-K for the year ended December 31, 2025 for a more complete description of the Company’s business and accounting policies. 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. Interim results are not necessarily indicative of results of operations for the full year. The consolidated balance sheet as of December 31, 2025 was derived from the Company’s audited annual consolidated financial statements. Intercompany transactions and balances have been eliminated. Discontinued Operations The results of operations of a component of the Company are reported in discontinued operations when certain criteria are met as of the date of disposal, or earlier if classified as held-for-sale. The Company determined that the sale of JRG Re, which closed on April 16, 2024, represented a strategic shift that had a major effect on the Company's operations. Accordingly, the results of JRG Re's operations have been presented as discontinued operations for all periods presented in this interim report on Form 10-Q. See Note 2 for additional disclosure. Estimates and Assumptions Preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying disclosures. Those estimates are inherently subject to change, and actual results may ultimately differ from those estimates. Variable Interest Entities Entities that do not have sufficient equity at risk to allow the entity to finance its activities without additional financial support or in which the equity investors, as a group, do not have the characteristic of a controlling financial interest are referred to as variable interest entities (“VIE”). A VIE is consolidated by the variable interest holder that is determined to have the controlling financial interest (primary beneficiary) as a result of having both the power to direct the activities of a VIE that most significantly impact the VIE’s economic performance and the obligation to absorb losses or the right to receive benefits from the VIE that could potentially be significant to the VIE. The Company determines whether it is the primary beneficiary of an entity subject to consolidation based on a qualitative assessment of the VIE’s capital structure, contractual terms, nature of the VIE’s operations and purpose, and the Company’s relative exposure to the related risks of the VIE on the date it becomes initially involved in the VIE. The Company reassesses its VIE determination with respect to an entity on an ongoing basis. The Company holds interests in VIEs through certain equity method investments included in “other invested assets” in the accompanying condensed consolidated balance sheets. The Company has determined that it should not consolidate any of the VIEs as it is not the primary beneficiary in any of the relationships. Although the investments resulted in the Company holding variable interests in the entities, they did not empower the Company to direct the activities that most significantly impact the economic performance of the entities. The Company’s investments related to these VIEs totaled $7.2 million at March 31, 2026 and $7.3 million at December 31, 2025, representing the Company’s maximum exposure to loss. Income Tax Expense The Company’s U.S. federal income tax expense differs from the amount computed by applying the federal statutory income tax rate of 21% to income before taxes primarily due to interest income on tax-advantaged state and municipal securities, dividends received income, and excess tax benefits and expenses on share based compensation. Prior to the Company's domestication from Bermuda to the U.S. on November 7, 2025, the Company's effective tax rate was impacted by the relative mix of income from continuing operations reported by country and the statutory tax rates of 0% and 21% imposed by Bermuda and the U.S., respectively. The Company did not receive a U.S. tax deduction for losses in Bermuda in the prior year period resulting from Bermuda holding company expenses and interest expense. For the three months ended March 31, 2026 and 2025, our effective tax rate on (loss) income from continuing operations was (17.5%) and 31.4%, respectively. The effective rate for the three months ended March 31, 2026 was below the federal statutory income tax rate of 21% primarily because of excess tax expenses on share based compensation. RSU awards vest on the anniversary of their grant date which are predominately in the first quarter of each year. Adopted Accounting Standards There were no new accounting standards adopted in 2026 that materially impacted the Company's financial statements. Prospective Accounting Standards The guidance in ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses requires additional, disaggregated disclosure around certain income statement expense line items. This ASU is effective for fiscal years beginning after December 15, 2026 and interim periods beginning after December 15, 2027, although early adoption is permitted. The Company is in the process of evaluating the impact of this new guidance on the disclosures in its financial statements. The guidance in ASU 2025-06, Intangibles-Goodwill and Other – Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software removes the concept of project stages and requires the capitalization of software costs when management has committed to funding the software project and it is probable that the project will be completed. This ASU is effective for fiscal years beginning after December 15, 2027, but early adoption is permitted as of the beginning of an annual reporting period. The Company is evaluating the impact of adopting this new guidance, but does not expect that the standard will have a material impact on our financial statements.

•James River Group is a Delaware domiciled insurance holding company formed in 2002, which owns all of the Company’s U.S.-based subsidiaries, either directly or indirectly through one of its wholly-owned U.S. subsidiaries. James River Group oversees the Company’s U.S. insurance operations.

•James River Insurance Company (“James River Insurance”) is an Ohio domiciled excess and surplus lines insurance company that, with its wholly-owned insurance subsidiary, James River Casualty Company, is authorized to write business in every state and the District of Columbia.

•Falls Lake National Insurance Company (“Falls Lake National”) is an Ohio domiciled insurance company which wholly owns Stonewood Insurance Company (“Stonewood Insurance”), an Ohio domiciled company, and Falls Lake Fire and Casualty Company, a California domiciled company. Falls Lake National and its subsidiaries primarily write specialty admitted fronting and program business.

The Company previously owned JRG Reinsurance Company Ltd. (“JRG Re”), a Bermuda domiciled reinsurer, which comprised the former Casualty Reinsurance segment, and which, prior to the suspension of its underwriting activities in 2023, primarily provided non-catastrophe casualty reinsurance to U.S. third parties. On November 8, 2023, the Company entered into an agreement to sell JRG Re. The sale closed on April 16, 2024 and resulted in the Company’s disposition of its casualty reinsurance business and related assets. The Company has no continued involvement with JRG Re following the sale. See Discontinued Operations below and Note 2 for additional disclosure.

The accompanying condensed consolidated financial statements and notes have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and do not contain all of the information and footnotes required by U.S. GAAP for complete financial statements. The condensed consolidated financial statements include the results of the Company and its subsidiaries from their respective dates of inception or acquisition, as applicable. Readers are urged to review the Company’s Annual Report on Form 10-K for the year ended December 31, 2025 for a more complete description of the Company’s business and accounting policies. 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. Interim results are not necessarily indicative of results of operations for the full year. The consolidated balance sheet as of December 31, 2025 was derived from the Company’s audited annual consolidated financial statements.

The results of operations of a component of the Company are reported in discontinued operations when certain criteria are met as of the date of disposal, or earlier if classified as held-for-sale. The Company determined that the sale of JRG Re, which closed on April 16, 2024, represented a strategic shift that had a major effect on the Company's operations. Accordingly, the results of JRG Re's operations have been presented as discontinued operations for all periods presented in this interim report on Form 10-Q. See Note 2 for additional disclosure.

Preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying disclosures. Those estimates are inherently subject to change, and actual results may ultimately differ from those estimates.

Entities that do not have sufficient equity at risk to allow the entity to finance its activities without additional financial support or in which the equity investors, as a group, do not have the characteristic of a controlling financial interest are referred to as variable interest entities (“VIE”). A VIE is consolidated by the variable interest holder that is determined to have the controlling financial interest (primary beneficiary) as a result of having both the power to direct the activities of a VIE that most significantly impact the VIE’s economic performance and the obligation to absorb losses or the right to receive benefits from the VIE that could potentially be significant to the VIE. The Company determines whether it is the primary beneficiary of an entity subject to consolidation based on a qualitative assessment of the VIE’s capital structure, contractual terms, nature of the VIE’s operations and purpose, and the Company’s relative exposure to the related risks of the VIE on the date it becomes initially involved in the VIE. The Company reassesses its VIE determination with respect to an entity on an ongoing basis.

The Company holds interests in VIEs through certain equity method investments included in “other invested assets” in the accompanying condensed consolidated balance sheets. The Company has determined that it should not consolidate any of the VIEs as it is not the primary beneficiary in any of the relationships. Although the investments resulted in the Company holding variable interests in the entities, they did not empower the Company to direct the activities that most significantly impact the economic performance of the entities. The Company’s investments related to these VIEs totaled $7.2 million at March 31, 2026 and $7.3 million at December 31, 2025, representing the Company’s maximum exposure to loss.

The Company’s U.S. federal income tax expense differs from the amount computed by applying the federal statutory income tax rate of 21% to income before taxes primarily due to interest income on tax-advantaged state and municipal securities, dividends received income, and excess tax benefits and expenses on share based compensation. Prior to the Company's domestication from Bermuda to the U.S. on November 7, 2025, the Company's effective tax rate was impacted by the relative mix of income from continuing operations reported by country and the statutory tax rates of 0% and 21% imposed by Bermuda and the U.S., respectively. The Company did not receive a U.S. tax deduction for losses in Bermuda in the prior year period resulting from Bermuda holding company expenses and interest expense. For the three months ended March 31, 2026 and 2025, our effective tax rate on (loss) income from continuing operations was (17.5%) and 31.4%, respectively. The effective rate for the three months ended March 31, 2026 was below the federal statutory income tax rate of 21% primarily because of excess tax expenses on share based compensation. RSU awards vest on the anniversary of their grant date which are predominately in the first quarter of each year.

The guidance in ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses requires additional, disaggregated disclosure around certain income statement expense line items. This ASU is effective for fiscal years beginning after December 15, 2026 and interim periods beginning after December 15, 2027, although early adoption is permitted. The Company is in the process of evaluating the impact of this new guidance on the disclosures in its financial statements.

The guidance in ASU 2025-06, Intangibles-Goodwill and Other – Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software removes the concept of project stages and requires the capitalization of software costs when management has committed to funding the software project and it is probable that the project will be completed. This ASU is effective for fiscal years beginning after December 15, 2027, but early adoption is permitted as of the beginning of an annual reporting period. The Company is evaluating the impact of adopting this new guidance, but does not expect that the standard will have a material impact on our financial statements.