The U.S. Department of the Treasury and Internal Revenue Service (IRS) today ruled that same-sex couples, legally married in jurisdictions that recognize their marriages, will be treated as married for federal tax purposes. The ruling applies regardless of whether the couple lives in a jurisdiction that recognizes same-sex marriage or a jurisdiction that does not recognize same-sex marriage.

The announcement has significant implications for Massachusetts employers, many of whom have maintained different tax and benefit processes for operations located in states that do not recognize same-sex marriage. The ruling may also benefit same-sex partners who run subchapter S corporations, limited liability corporations and other entities that pay taxes at the individual level.

Under the ruling, same sex couples will be treated as married for all federal tax purposes, including income and gift and estate taxes. The ruling applies to all federal tax provisions where marriage is a factor, including filing status, claiming personal and dependency exemptions, taking the standard deduction, employee benefits, contributing to an IRA, and claiming the earned income tax credit or child tax credit.

Any same-sex marriage legally entered into in one of the 50 states, the District of Columbia, a U.S. territory, or a foreign country will be covered by the ruling. However, the ruling does not apply to registered domestic partnerships, civil unions, or similar formal relationships recognized under state law.

Legally-married same-sex couples generally must file their 2013 federal income tax return using either the “married filing jointly” or “married filing separately” filing status.

Individuals who were in same-sex marriages may, but are not required to, file original or amended returns choosing to be treated as married for federal tax purposes for one or more prior tax years still open under the statute of limitations.

Generally, the statute of limitations for filing a refund claim is three years from the date the return was filed or two years from the date the tax was paid, whichever is later. As a result, refund claims can still be filed for tax years 2010, 2011, and 2012. Some taxpayers may have special circumstances (such as signing an agreement with the IRS to keep the statute of limitations open) that permit them to file refund claims for tax years 2009 and earlier.

Additionally, employees who purchased same-sex spouse health insurance coverage from their employers on an after-tax basis may treat the amounts paid for that coverage as pre-tax and excludable from income.

Click here to read the Revenue Ruling 2013-17, along with updated Frequently Asked Questions for same-sex couples and updated FAQs for registered domestic partners and individuals in civil unions, are available today on IRS.gov. See also Publication 555, Community Property

Treasury and the IRS will begin applying the terms of Revenue Ruling 2013-17 on September 16, but taxpayers who wish to rely on the terms of the Revenue Ruling for earlier periods may choose to do so (as long as the statute of limitations for the earlier period has not expired).

Please note: Your state tax liability may be affected by a change made on your federal return. For information on how to correct your state tax return please reference the Department of Revenue’s website for updates.