
After seventy five years, alimony will no longer be deductible by the payor spouse, nor taxable to the payee--a dramatic change which will have a significant impact on divorcing couples and their ability to negotiate a fair settlement.
Alimony or spousal support in varying terms and amounts is not uncommon in divorce or legal separation when the marriage is of significant length, or where there's a substantial discrepancy in income and/or education, health issues or aging parties. It's also not unusual when a couple has preschool children, and a stay-at-home parent who cannot reasonably balance the cost of childcare with earnings.

This may seem like good news to the receiver of spousal support, but it's likely the courts will take the lack of deductibility into account when awarding alimony. Certainly mediators and financial experts, who typically "tax effect" support payments, will do so. The net effect will be that there will be less income to spread amongst two households.
Called the Tax Cuts and Jobs Act of 2017, perhaps the new law should named the Better Get a (Second) Job Act. Either the payor is going to need some extra income, or the recipient will need to supplement--or both.

Beginning in 2019, alimony will be treated the same as child support--nontaxable to the recipient. The tax treatment of child support will not change.
This seems to contrary to the theme of "Tax Cuts." So what was Congress' rationale? The House Ways and Means Committee termed the alimony deduction a “divorce subsidy.” “A divorced couple can often achieve a better tax result for payments between them than a married couple can.”

So, if it looks like you are about to pay alimony, hope that
your decree is signed before the end of 2018 or that your lower earning spouse hits the lottery.
December's going to be very busy.
MORE ABOUT THE MONEY:
The Cost of Divorce
It's Not About the Money!