The Thailand Office of Insurance Commission has approved changes to the calculation of premium reserves for short-term insurance contracts and the related risk capital requirement, shifting the assessment from an insurer-wide aggregate basis to an underwriting category basis to better reflect underlying risk and align with international standards. The Insurance Commission’s 22 May 2025 resolution endorsed amendments to three related notifications covering annual reporting requirements for policy liability calculations for non-life insurers, annual reporting requirements for policy liability calculations for life insurers, and the types and calculation of capital for non-life insurers. The revised methodology calculates both the premium reserve and capital for the risk from premium reserves by type of underwriting business rather than across all short-term contracts, aiming for more granular and accurate measurement and capital allocation. Input was gathered through a consultation held 6–21 March 2025, briefing meetings on 10–11 March 2025, and a technical focus group concluded on 18 April 2025. The Office will publish the amended notifications formally in due course, with the updated requirements scheduled to take effect on 31 December 2025.