I'm divorced. If I'm paying alimony to my ex, and I'm not claiming it as a deduction, does she have to claim it as income?

[mrgoldy]

I read that  Spousal support must be reported as taxable income by the recipient and can be deducted by the paying spouse, unless you agree otherwise

So that unless you agree otherwise part,  means if we decide not to claim the income or the deduction on either end,  that's our choice?

[KenH1]

FOR TAX YEAR 2018 AND PRIOR

Yes, she does.  You are not required to deduct it, but she should claim it as income (unless it's actually child support, see below)

Spousal support (alimony) is both taxable to the recipient and deductible for the payer.  

Child support income is not taxable, nor is it deductible for the payer.