If two individuals were considering marriage after college, what would the actual tax benefits be? Both are male. Both have full time jobs. In the United States.
This depends greatly on both your total income and especially your income relative to each other. If you have very different incomes, then you'll get a bonus. Generally speaking, if you have substantially similar incomes, you will essentially pay a penalty regardless of your total income. The effect is actually pretty complicated because of the factors involved. There's a decent summary that's current here:
The details can change with the tax code, so the answer to this question changes over time.
Brick was on the right path, but it's also about the level of income. If two $45K earners marry, there's no tax benefit or penalty. As incomes rise, you can see, a marriage penalty kicks in. Two high earners can do the math to see what the joy of marriage costs, in dollars and cents. (The numbers below reflect 2016 tax rates)