How do I deduct spousal support from my taxes?

Go to Alimony paid (under Deductions& Credits>Other deductions and credits > alimony paid, and enter your data there. 

Unfortunately, spousal support is not a deductible expense.

 

If you pay Alimony (spousal support), Alimony payments resulting from agreements executed after that date can no longer be deducted due to the Tax Cuts and Jobs Act (TCJA) that Congress signed into law on December 22, 2017. The same holds true for agreements modified after 2018 if the new version specifically states that the TCJA treatment of nondeductible alimony payments now applies.

How the IRS defines alimony payments

 

To qualify as alimony or separate maintenance, the payments you make to your former spouse must meet all six of these criteria:

1. You don't file a joint tax return with your former spouse.
2. You make payments in cash, by check, or by money order.
3. You make payments to or for a spouse or former spouse under an applicable divorce or legal separation agreement.
4. Legally separated spouses cannot be part of the same household when making payments.
5. Liability for the payment doesn't extend beyond the death of the spouse who receives payments.
6. The payment is not child support or a property settlement.

Filing Taxes After a Divorce: Is Alimony Taxable?