The U.S. Supreme Court held that Section 3 of the Defense of Marriage Act, which required same-sex spouses to be treated as unmarried for purposes of federal law, was unconstitutional.
The IRS will recognize as married for federal tax purposes same-sex couples who are married in a state, the District of Columbia, a U.S. territory, or a foreign country that authorizes same-sex marriages, regardless of the couple’s current domicile (state of celebration rule) and will not recognize as married for federal tax purposes same-sex couples or opposite-sex couples who have entered into a registered domestic partnership, civil union, or other similar formal relationship that is not denominated as a marriage under the laws of that state.
Couples that fall under these rules above will have to file their federal tax returns as either married filing jointly or married filing separately. If they live in a state that does not recognize same sex marriage, they will each file a single tax return for the state.
This ruling affects over 1,138 federal statuary provisions in the U.S. code where “benefits, rights and privileges are contingent on marital status or in which marital status is a factor”.
For example, the ruling will affect estate planning, gifting, pension and retirement plans, filing thresholds for foreign financial accounts, and employee benefit plans to list a few.