Some wealthy and low-income married couples are losing out at tax time, but experts say eliminating the so-called marriage penalty is more complicated than you might think.
"It's just impossible to get rid of it with the tax system that we've got," said Roberton Williams, senior fellow at the Tax Policy Center think tank.
That's because the U.S. tax system is progressive, meaning that people pay more taxes as their incomes go up, and also factors in whether people are married or single when it comes to filing taxes.
Williams suspects that more couples get a marriage bonus than a marriage penalty, meaning that their overall tax bill is lower because they are married. But he said there's no question that some people would have a lower tax bill if they were single instead of married.
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And despite an effort in the early 2000s to decrease the group of people subject to the marriage penalty, some couples are still caught by it.
At this point, researchers say those are mainly high-income couples with similar earnings who are bumped into higher tax brackets because of their joint earnings, or lower-income couples who lose out on tax benefits and other social assistance once they combine incomes.