Operators set the headline jackpot a week (or several days) before the draw closes, based on projected ticket sales. As the week progresses, actual sales data flows in. If sales are stronger than projected, the final jackpot lifts upward; if weaker, the operator absorbs the gap and pays the headline figure anyway — but only if Division 1 is won.
When Division 1 isn't won, the entire prize pool rolls into the next draw's headline jackpot. Because rollovers compound, the headline grows fast: a A$3M base + A$5M of unsold rollover produces a A$8M next-week estimate, plus whatever next week's projected sales add.
On Powerball Australia and Oz Lotto, the headline can grow midweek if sales accelerate. The Lott updates its public-facing figures multiple times before draw close — that's why your Tuesday morning Powerball poster might read $80M and Thursday's says $100M.
After the draw, the 'final' jackpot is what was actually paid (or rolled). When there's a single winner, this number is the prize they take home. When multiple winners share Division 1, the final is the per-winner amount, and the operator publishes both the per-winner share and the total Division 1 pool separately.
When you're comparing draws or looking at historical records (see our /records pages), final amounts are the truth-on-the-page. Estimated jackpots are useful for ticket buying — they tell you what's at stake before you commit — but for after-the-fact comparison the final figure is what counts.
If a draw has no Division 1 winner, the 'final' jackpot is reported as Rollover and the prize pool slides into next week's headline. On NZ Lotto + Powerball Must-Be-Won draws, no rollover is possible: the entire pool must be paid out, sliding down to the highest division that did have winners.