When filing as "married filing joint" how do you figure each spouses portion of the taxes due or refund? As an example:
Husband's taxable income is 100,000
Wife's taxable income is 50,000
Using standard deduction of 29,200, that brings the household income to 120,800.
This brings the husband's adjusted income to 80,436 (100,000 - 67% of standard deduction)
and the wife's adjusted income to 40,364 (-33% of standard deduction)
This means the husband's Fed tax bill would be 17,695 (22% marginal rate)
and the wife's portion would be 8,880. The husband would pay/get refunded any amount withheld from his income above or below the 17,695 and the wife the same for the 8,880.
Does this look like a fair way to split the two incomes when filing jointly?
Your question is more about your relationship than about taxes. What is “fair” is what is acceptable to both of you.
When you file a joint tax return, you are agreeing to combine all of your income, your dependents (if any) your deductions and credits, etc. etc. on one tax return. Your tax due or refund is not broken down "per spouse"--if there is a refund it comes with both names on it. When you said "I do" you agreed to share. The two of you have to decide what seems "fair" to each of you.