Same-sex married couples may get a tax break from Democrats’ $1.75 trillion social and climate spending plan.

The latest iteration of the Build Back Better Act would let taxpayers who were legally married under state law before 2010 claim federal tax benefits that are unavailable under current rules.

Essentially, the revision would let couples file amended tax returns for years as early as 2004. They could file a joint federal return as a married couple, and claim refunds and credits that may result in a net tax benefit.  

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“It’d be pretty significant for some folks,” said Jeffrey Levine, an accountant and certified financial planner at Buckingham Wealth Partners in Long Island, New York.

Democrats’ legislation, which the House aims to pass this week, may change and its ultimate success isn’t guaranteed.

United States v. Windsor

However, same-sex marriage was legal in five states (Connecticut, Iowa, Massachusetts, New Hampshire and Vermont) plus Washington, D.C., before 2010, according to the Pew Research Center.

(Massachusetts became the first state to legalize the unions, in 2003, after its Supreme Judicial Court ruled that the state constitution gives gay and lesbian couples the right to marry, according to Pew; weddings began in 2004. The U.S. Supreme Court later legalized same-sex marriage nationwide, in 2015, in Obergefell v. Hodges.)

Gay and lesbian couples who legally wed before 2010 would be able to file an amended tax return if Congress passes the Build Back Better Act with the provision intact.

“This is a fair thing to do,” said Steve Wamhoff, director of federal tax policy at the Institute on Taxation and Economic Policy. “People were married [but] the federal government wasn’t recognizing their marriages.”

While fair in terms of tax policy, it’s questionable whether many couples would make the effort to redo their tax returns and take advantage of new rules, Wamhoff said.

Marriage penalty

For example, in 2004, single taxpayers were in the 28% tax bracket if their income exceeded $70,350. However, instead of a level twice that amount, married couples filing a joint tax return hit the 28% rate once income exceeded $117,250.

That basically meant married couples jumped into that tax rate more easily with respect to their income. (There’s still a marriage penalty, but a federal tax law in 2017 temporarily eased it.)

Married couples may also be able to claim certain tax benefits unavailable to single filers, Levine said.

For example, if a higher-earning spouse had paid for medical or education expenses for the other spouse pre-2010, the high earner couldn’t claim medical or education tax breaks for those costs on their individual return, Levine said. They’d perhaps be able to do so on a married-joint return.