This article clarifies information provided on page 10 of IRS Publication 5307, Tax Reform Basics for Individuals and Families for the repeal of deduction for alimony payments under the Tax Cuts & Jobs Act of 2017.
Alimony or separation payments paid to a spouse or former spouse under a divorce or separation agreement, such as a divorce decree, a separate maintenance decree, or a written separation agreement, may be alimony for federal tax purposes. Alimony or separation payments are deductible if the taxpayer is the payer spouse. Receiving spouses must include the alimony or separation payments in their income.
Beginning Jan. 1, 2019, alimony or separate maintenance payments are not deductible from the income of the payer spouse, or includable in the income of the receiving spouse, if made under a divorce or separation agreement executed after Dec. 31, 2018.
This also applies to a divorce or separation agreement executed on or before Dec. 31, 2018, and modified after December 31, 2018, as long as the modification:
changes the terms of the alimony or separate maintenance payments; and states that the alimony or separate maintenance payments are not deductible by the payer spouse or includable in the income of the receiving spouse.
On the other hand, generally alimony or separate maintenance payments are deductible from the income of the payer spouse and includable in the income of the receiving spouse, if made under a divorce or separation agreement executed on or before Dec. 31, 2018, even if the agreement was modified after December 31, 2018, so long as the modification is not one described in the preceding paragraph.