In a far-reaching response to the U.S. Supreme Court striking down natural marriage laws last summer in Obergefell v. Hodges, the IRS and Department of the Treasury have changed the meanings of the words “spouse,” “marriage,” “husband” and “wife.” This change was also a response to the Court’s 2013 decision in United States v. Windsor, which ruled that the words “spouse” and “marriage” could not be limited to heterosexual marriages.

IRS Regulation Section 301.7701-18

For federal tax purposes, the terms spouse, husband, and wife mean an individual lawfully married to another individual. The term husband and wife means two individuals lawfully married to each other. A marriage of two individuals is recognized for federal tax purposes if the marriage would be recognized by any state, possession, or territory of the United States.

“Husband” and “wife” now refers to “two individuals lawfully married to each other,” regardless of sex. The new definitions will give same-sex marriage couples job-protected leave to take care of their spouse’s family members under the Family and Medical Leave Act, and applies to the marital status of taxpayers for purposes of the income, estate, gift, excise and payroll taxes.

Of course, same-sex couples will now also face the “marriage penalty” for filing their taxes jointly. The “penalty” is the higher tax rate some married couples must pay if they are a middle to upper class couple with roughly similar incomes.

The proposed rule changes were announced in October, left open for comment, and finalized on Friday, with barely any fanfare or objections. One submitted comment to the proposed rule — to replace the words “husband” and “wife” with “spouse” — might have made more sense. Congress could still make that change in the future.

Another commenter suggested the IRS include the words “same-sex marriage” to better explain the changes, but the IRS dismissed the concern. According to The Washington Examiner, “Treasury and the IRS believe that the definitions in the proposed regulations apply equally to same-sex couples and opposite-sex couples, and that no clarification is needed. Amending the regulations to specifically address a marriage of two individuals of the same sex would undermine the goal of these regulations to eliminate distinctions in federal tax law based on gender.”

The changes do not apply to domestic partnerships or civil unions, in order to allow couples to choose alternative tax treatment that might benefit them more than being married.

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