I just want to point out that this whole tax business is utter garbage. Married couples today are much more likely to get a tax penalty than a tax benefit, because they both work.
See, there are 4 tax schedules: http://www.fourmilab.ch/ustax/www/t26-A-1-A-I-1.html
As you can see, single individuals are treated the worst.
So imagine Bob makes 53,500, and Jane makes nothing. If they don’t get married, then Bob pays 12,107 in taxes. But if they get married, then together they only pay 10,183. That is the marriage benefit.
But, imagine that Bob makes 53,500 and Jane also makes 53,500. If they live together unmarried, then each pays 12,107 in taxes, for a total of 24,214 for the two of them. But if they get married, then they have income together of 107,000 and pay in taxes 25,698.50 which is more than they would pay together if they were unmarried. And that is the marriage penalty.
Most households today are two earner households, and have the marriage penalty. Interestingly if you live in a state that recognizes gay “marriage,” you don’t get the marriage penalty since the feds don’t recognize it.