On August 29, the U.S. Department of the Treasury (Treasury) and the Internal Revenue Service (IRS), following the U.S. Supreme Court’s decision in United States v. Windsor, jointly announced the issuance of Revenue Ruling 2013-17 (the Ruling), providing guidance on the federal taxation of same-sex couples. Windsor invalidated, on equal protection grounds, the limitation of marriage to opposite-sex couples in the Defense of Marriage Act (DOMA). The Ruling holds that for all federal tax purposes, including income, gift and estate tax, the IRS will recognize same-sex marriages that are legally valid in the jurisdiction where the couple married, regardless of whether the state in which the couple resides would recognize the marriage.

Citing the need for uniformity in federal tax law and the administration of employee plans, the Ruling answers the most fundamental question that employers, individual taxpayers and others had following Windsor: whether the law of the state of a same-sex couple’s domicile or the law of the state in which they entered into their marriage would control their status for federal tax purposes. The Ruling specifically says that same-sex marriages legally entered into in any state that recognizes such marriages, including the District of Columbia, a U.S. territory, or a foreign country, will be recognized for all federal tax purposes. The Ruling does not, however, extend to same-sex couples in registered domestic partnerships or civil unions.