IRS: Married gay couples can file joint tax returns

• Decision follows Supreme Court ruling in June
• All married couples will qualify%2C even if they have moved
• But not all couples will come out ahead on their taxes

WASHINGTON — Married same-sex couples will be treated the same as opposite-sex couples for tax purposes, the Obama administration announced Thursday, regardless of where they live now.

The Treasury Department, following up on the Supreme Court's ruling in June striking down a key section of the 1996 Defense of Marriage Act, announced that gay and lesbian married couples can file joint federal tax returns.

Importantly, the government said those couples can do so even if they have moved to states that do not permit same-sex marriages — although they may have to file their state tax returns as if they were not married, depending on state laws. The same is not true for Social Security, which will only recognize couples living in states that allow same-sex marriages.

Thirteen states and the District of Columbia permit same-sex couples to marry. The states are California, Connecticut, Delaware, Iowa, Maine, Maryland, Massachusetts, Minnesota, New Hampshire, New York, Rhode Island, Vermont and Washington.

Treasury Secretary Jacob Lew said the new rules, which take effect Sept. 16, will provide "clear, coherent tax-filing guidance for all legally married same-sex couples nationwide."

Not all same-sex couples will benefit from the decision; some may pay higher income taxes as a result of the "marriage penalty." All will have the opportunity to amend their tax returns from 2010-12 — but only if they choose.

The high court ruling came in a case filed by Edie Windsor, an octogenarian from New York who was forced to pay $363,000 in federal estate taxes after the death of her lesbian spouse, Thea Spyer. The court upheld lower courts in justifying her claim against the law passed by Congress during the Clinton administration.

The new Treasury-Internal Revenue Service guidelines will apply to all federal taxes, including income, gift and estate taxes. They affect personal and dependent exemptions and deductions, employee benefits, IRA contributions and tax credits.

The biggest financial bonanza for some couples will be the tax exclusion for employer-paid health insurance, which many same-sex spouses previously bought on an after-tax basis. That could be worth more than $1,000 per couple.

"This is uniformly good for everybody," said Todd Solomon, a lawyer who specializes in pension plans and benefits. "Their health benefits just went from taxable to non-taxable."

Chad Griffin, president of the Human Rights Campaign, the nation's largest gay-rights group, said same-sex families "finally have access to crucial tax benefits and protections previously denied to them under the discriminatory Defense of Marriage Act."

The new guidelines will not affect couples who are in civil unions or domestic partnerships rather than legal marriages.

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