Prenups Under Attack as Tax Law Boosts Cost of Alimony Payments

• Divorce lawyers weigh revisiting agreements for happy couples • Top earners could effectively pay double in post-tax expenses

President Donald Trump’s tax overhaul could wreak havoc on prenuptial agreements across the country -- and maybe even his own.

Prenups often contain provisions about how much a partner would pay in alimony, also known as spousal support. The agreements can be thrown out if judges deem them unfair, signed too quickly or under duress. Now the tax revamp offers another avenue for challenges because courts will likely have to consider how the law has changed since the contracts were created. Starting in 2019, ...