Does every rollover raise EV?

Yes, up to a point. Beyond it, higher ticket volume drags EV back down via split risk.

Where is the EuroJackpot inflection?

After 2 consecutive cap weeks (€120M), EV peaks. After 3+, split risk dominates.

Where is the Powerball inflection?

Around $400M. Beyond that, EV per ticket falls again.

Does cap overflow make EV positive?

Often yes. EuroJackpot overflow goes to lower tiers with much less split risk.

How do I measure split risk myself?

P(at least one winner this draw) × expected number of winners conditional on you winning. Tracker handles it automatically.

What a Rollover Really Does to EV and Split-Risk

A rollover sounds like free money — last week's jackpot didn't get won, so this week is bigger. In practice, rollovers move two numbers in opposite directions: expected value goes up, split-risk also goes up. Whether they net out positive depends on the game.

For the full EV formula — every prize tier, worked out for EuroJackpot — see our lottery expected value guide.

The mechanism

When nobody hits the top tier, that prize pool carries forward. After enough rollovers (or a cap-breaker week), the jackpot is so large that:

EV per ticket may turn positive.
Ticket sales explode — sometimes 5–10× a normal week.
More tickets sold = more lines competing for the same jackpot if you win = higher chance of splitting.

A worked example: EuroJackpot, €17M → €120M (cap)

| Jackpot | Tickets sold | P(jackpot) | P(other wins jackpot | you win) | Your EV per €2 line | |---|---|---|---|---| | €17M (base) | ~25M | 1/139.8M | low | ~€0.95 | | €60M | ~70M | 1/139.8M | ~28% | ~€1.20 | | €120M (cap) | ~180M | 1/139.8M | ~57% | ~€1.40 (still positive after split risk) |

EV stays positive at the cap because the cap forces overflow into lower tiers, which you can still hit without splitting them with as many people.

When rollovers go negative for you

Some games (US Powerball at $1B+) sell so many tickets that:

P(at least one winner this draw) > 80%
Conditional on you winning, expected split ≈ 2.3 ways
EV per ticket: lower than a $400M jackpot drew

The "biggest jackpot ever" headlines are usually the worst EV moments of that game's cycle.

The single rule

For European 5-of-50 + 2-of-12 games (EuroJackpot, EuroMillions): rollovers help up to the cap. After the cap is hit twice in a row, EV peaks. After 3+ cap weeks, split risk dominates.

For US Powerball / Mega Millions: rollovers help up to ~$400M. Beyond that, split risk dominates and EV per ticket falls.

How to use this

Set EV alerts on your tracker for: (a) jackpot crosses the cap threshold, (b) cap-overflow distributions activate, (c) jackpot crosses $400M for US games.

Buy lines only inside those windows. Skip every other week.

Bottom line

Rollovers don't always raise EV. They raise the jackpot, which raises EV up to a point and split-risk past it. Know where the inflection is for each game and only play inside the window.