Mega Millions is one of two major multi-state lottery games in the U.S. (the other being Powerball), sold in 45 states plus Washington D.C. and the U.S. Virgin Islands. Because so many states pool their ticket sales into one shared jackpot, Mega Millions has produced some of the largest lottery prizes in history, including several jackpots over $1 billion. The game launched in its current 5-numbers-plus-Mega-Ball format in 2002 and has been tweaked several times since — most notably the 2025 change that widened the Mega Ball pool and added a built-in 2x multiplier on every ticket.
The jackpot starts at a set minimum and grows every time a drawing passes without a winner, funded by a portion of ticket sales from that drawing plus the roll-forward amount from before. That's why jackpots tend to snowball — more media attention drives more ticket sales, which adds more money to the pot even before accounting for the standard rollover. If nobody matches all six numbers, the jackpot simply carries over to the next drawing and keeps growing until someone does.
Winners of the jackpot choose between the full prize paid out as an annuity over 29 years, or a reduced lump sum paid immediately — the lump sum is the present cash value of the jackpot, generally somewhere around half to 60% of the advertised amount before taxes. Federal withholding of 24% applies automatically to any prize over $5,000, and most states add their own withholding on top of that. Smaller prizes, from $2 up to $10,000, can typically be claimed right at the retailer where the ticket was purchased or at any other licensed lottery retailer in the state.