From The Big Game (1996) to today — how rule changes stretched the jackpot odds.
| Start date | White balls | Mega Ball | Jackpot odds | Notable changes |
|---|---|---|---|---|
| Sep 6, 1996 | 5 / 50 | 1 / 25 | 1 in 52,969,000 | The Big Game launches (six states) |
| Jan 13, 1999 | 5 / 50 | 1 / 36 | 1 in 76,275,360 | Special-ball pool increases |
| May 15, 2002 | 5 / 52 | 1 / 52 | 1 in 135,145,920 | Renamed Mega Millions; matrix expands |
| Jun 22, 2005 | 5 / 56 | 1 / 46 | 1 in 175,711,536 | Further expansion |
| Oct 19, 2013 | 5 / 75 | 1 / 15 | 1 in 258,890,850 | Matrix overhaul; $1M second prize introduced |
| Oct 28, 2017 | 5 / 70 | 1 / 25 | 1 in 302,575,350 | Ticket price to $2; higher non-jackpot prizes |
| Apr 8, 2025 | 5 / 70 | 1 / 24 | 1 in 290,472,336 | Built-in 2×–10× multipliers; ticket $5 |
Dates reflect official change/effective or first-draw dates from Mega Millions and state lottery releases; early Big Game entries reflect published historical tables.
Key references used to compile this page:
This is an educational summary and may omit minor interim tweaks. Always verify current rules on your state lottery site.