It depends on the country that you resides in. Some have preferential tax treatments. Consult a CPA. When you go to Vegas, usually the big tournaments will have a CPA booth at the tournament. I know that's true for the WSOP.
To prove my point, check out the article linked below. Nick Marchington (England) paid $0 in taxes on his $1.5M, but Milos Skrbic (Serbia) paid $474K on his $1M winnings.
http://www.taxabletalk.com/2019/07/...al-winners-of-the-2019-world-series-of-poker/
Please support Russ by going directly to his blog. If you are parinod like myself, the poker news article is linked here.
https://www.pokernews.com/news/2019...-main-event-final-table-players-tax-34912.htm
Seeing this has made me so glad I’m in England! I would definitely be refusing to pay anything near those taxes!