Effective September 2, 2016, the Internal Revenue Service formally put into place amendments to regulations that define who is married for tax purposes. The new regulations finalize proposed regulations issued in 2015, with only a few minor changes. The IRS Regulation states that it will interpret the term “husband and wife” as any two people who are married to each other, even if they are a same-sex couple.

The IRS moved to address these issues after two landmark cases: the 2013 Supreme Court ruling in United States v. Windsor, that struck down the section of the Defense of Marriage Act (DOMA) prohibiting recognition of same-sex marriages for federal purposes and the 2015 Supreme Court ruling in Obergefell v. Hodges that made same-sex marriage legal throughout the nation.