The biggest known sports bet win was $1.2M. James Adducci placed an $85K wager on Tiger Woods’ Masters in 2019 and won. Adducci maintains that this was his very first sports bet.
However, the biggest wager ever placed was $5.9 million. This bet was placed by none other than Floyd Mayweather, a famous boxing star. He betted on the win of the Miami Heats in 2013 and won around $590,000.
If you want to learn more about how betting odds work in boxing, check out our boxing section above.