But there's a "tremendous" long-term tax benefit for lottery winners, with tax reform provisions that would eliminate the estate tax or make it easier to avoid, Kurland said.
Both the House and the Senate versions would double the amount a wealthy individual can transfer in death tax-free, to about $11 million. The House goes a step further, setting the estate tax to disappear at the end of 2024.
"The benefit for lottery winners is huge, because the estate tax is really targeted toward people like this," he said.
The key takeaway for jackpot hopefuls: Next year, it will become even more important to make sure you're putting together an expert team (accountant, financial advisor and attorney) ahead of claiming the prize, who can help you strategize how to claim the win and maximize your take-home amount.
Only part of your federal and state tax burdens are withheld upfront, and it's important to figure out the whole tab quickly, Bradley said. (See infographic below.) Miscalculating the final tax bill can be an expensive misstep for winners trying to figure out how to save or spend their haul.
"At the end of the day, it's all about net numbers," she said.
More from Personal Finance:
This interactive chart shows how the GOP tax plan will hit your wallet
Here's what the Senate's tax bill means for your wallet
Before you ring in 2018, make these big-money tax moves