If we renegotiated alimony in January 2024, with a new legal agreement, doI still have to claim it as income?

• For Pre-2019 Agreements:Remain deductible/taxable unless both parties explicitly agree to follow the post-2018 rules. Modifications alone do not automatically change the tax treatment—only if the new agreement explicitly states it follows post-2018 rules.

No. Since your new agreement is dated 2024, then you will fall under the new tax laws. This is considered a modification.

Filing Taxes after Divorce: Is Alimony Taxable?

• Alimony taxation: Today, alimony or separate maintenance payments relating to any divorce or separation agreements dated January 1, 2019, or later are not tax-deductible by the person paying the alimony. The person receiving the alimony does not have to report the alimony received as taxable income.
• IRS Topic 452 - Alimony and Separate Maintenance

Read the IRS rules here:

https://www.irs.gov/newsroom/divorce-or-separation-may-have-an-effect-on-taxes

The last paragraph answers your question.