IRS Provides Guidance on Substitute Mortality Tables

The Internal Revenue Service has released Revenue Procedure (Rev. Proc.) 2025-21, which provides guidance on plan-specific substitute mortality tables used to determine the present value for defined benefit plans subject to funding requirements under IRC. Sec. 430. The revenue procedure modifies Section 12.02 of Rev. Proc. 2024-32, which specifies when certain plan sponsors are required to terminate the use of plan-specific mortality tables. Rev. Proc. 2025-21 provides relief for certain plan sponsors by narrowing the category of plan sponsors that are required to request approval of new plan-specific substitute mortality tables.

Specifically, Section 12.02 of Revenue Procedure 2024-32 indicates that plans with significant changes in coverage will be required to terminate a previously approved substitute mortality table for periods after January 1, 2026. Rev. Proc. 2025-21 provides an exception to this rule by providing an exception for plans using a mortality ratio determined with combined genders in certain circumstances, so long as the plan actuary certifies that the tables used continue to be accurately predictive of the population’s future mortality.

This revenue procedure is effective for all requests for approval to use plan-specific substitute mortality tables that apply beginning on or after January 1, 2026.