If a safe harbor 401(k) or 401(m) plan needs to be updated to comply with the U.S. Supreme Court’s Windsor decision, which recognizes the marriage of same-gender couples under federal law, they have an exception to the typical beginning-of-the-plan-year time frame for plan amendments, according to the IRS.
Following the Windsor decision, plans need to be amended if, for example, they define the term “spouse” as only a person of the opposite sex (see “Not All Retirement Plans Must Be Amended for Windsor”). A plan must also be amended if the plan sponsor chooses to reflect the outcome of Windsor for periods prior to the date Windsor was decided.
According to the IRS, required amendments must generally be adopted by the later of December 31, 2014, or the applicable date under the IRS’ general amendment guidance for qualified retirement plans, Revenue Procedure 2007-44.
More information from the IRS about mid-year amendments in relation same-gender couples can be found here.