The industry and where the money goes

The History of Jackpot Inflation: Every Major Matrix Change, With the Odds Derived

A dated record of the redesigns that lengthened the world's biggest lottery odds, with every odds figure derived from the published matrix rather than repeated.

The jackpot odds on the world's largest lottery games have been lengthened repeatedly and deliberately. This is the record, with dates, and with every odds figure derived from the matrix rather than copied from a press release.

The method throughout is the standard combination count, set out in how lottery odds are calculated. For a game where you pick k numbers from a pool of n plus one supplementary from a separate pool of s:

Combinations = C(n, k) × s, where C(n, k) = n! ÷ (k! × (n − k)!)

US Powerball — 4 October 2015

Tickets for the new game went on sale Sunday 4 October 2015, with the first draw on Wednesday 7 October (NC Education Lottery). The white-ball pool went from 59 to 69; the Powerball pool from 35 to 26.

Before After
Matrix 5 of 59 + 1 of 35 5 of 69 + 1 of 26
C(n, 5) 5,006,386 11,238,513
× supplementary pool × 35 × 26
Jackpot odds 1 in 175,223,510 1 in 292,201,338
Overall odds of any prize 1 in 32 1 in 25

Longer by a factor of 292,201,338 ÷ 175,223,510 = 1.668. Cost of covering every combination at $2 a line: $350.4m before, $584.4m after.

US Mega Millions — 28 October 2017

The price doubled from $1 to $2, the main pool shrank from 75 to 70, and the Mega Ball pool grew from 15 to 25, from the draw of 28 October 2017 (Lottery.net).

Before After
Matrix 5 of 75 + 1 of 15 5 of 70 + 1 of 25
C(n, 5) 17,259,390 12,103,014
× supplementary pool × 15 × 25
Jackpot odds 1 in 258,890,850 1 in 302,575,350
Ticket price $1 $2

Odds longer by 1.169×, price doubled. Cost to cover the matrix: $258.9m before, $605.2m after — 2.34× more expensive for one guaranteed jackpot.

US Mega Millions — 5 April 2025

The most interesting entry in the list, because it goes the other way on odds and much further on price. From 5 April 2025 the Mega Ball pool shrank from 25 to 24 and the price rose from $2 to $5 (Louisiana Lottery).

Before After
Matrix 5 of 70 + 1 of 25 5 of 70 + 1 of 24
Jackpot odds 1 in 302,575,350 1 in 290,472,336
Overall odds 1 in 24 1 in 23
Ticket price $2 $5
Starting jackpot $20m $50m

The odds got 4% shorter. The price rose 150%. Multiply the two and the cost of covering the matrix goes from 302,575,350 × $2 = $605.2m to 290,472,336 × $5 = $1,452.4m2.40× more. Every ticket also carries a built-in 2×–10× multiplier on non-jackpot prizes, which is where a good part of the extra $3 goes.

This is the same manoeuvre as a matrix lengthening, executed through price instead of combinatorics. The result on the jackpot side is identical: more money per unit of jackpot chance, therefore a faster-growing and larger headline number.

UK Lotto — 3 October 2013 and 10 October 2015

The UK ran the two levers separately, two years apart.

Lotto launched on 19 November 1994 as 6 from 49 at £1 a line. The price doubled to £2 from 3 October 2013 with the matrix untouched. Then from 10 October 2015 the pool went from 49 to 59.

1994–2013 2013–2015 From Oct 2015
Matrix 6 of 49 6 of 49 6 of 59
Combinations C(49,6) = 13,983,816 13,983,816 C(59,6) = 45,057,474
Ticket price £1 £2 £2
Cost to cover the matrix £13.98m £27.97m £90.11m

Odds longer by 45,057,474 ÷ 13,983,816 = 3.222×. Combined with the price doubling, the cost of buying one guaranteed jackpot rose 6.44× in 21 years. (National Lottery history; current rules on the UK Lotto odds page.)

EuroMillions — May 2011 and September 2016

EuroMillions has never changed its main matrix. It has changed the Lucky Star pool twice, which is enough.

Era Matrix C(50,5) × C(s,2) Jackpot odds
From launch (2004) 5 of 50 + 2 of 9 2,118,760 × 36 1 in 76,275,360
From May 2011 5 of 50 + 2 of 11 2,118,760 × 55 1 in 116,531,800
From September 2016 5 of 50 + 2 of 12 2,118,760 × 66 1 in 139,838,160

Two extra Lucky Stars, added twelve years apart, lengthened the odds by 1.833× in total — from adding three balls to a pool of nine. That is the leverage a small secondary pool gives an operator: C(11,2)/C(9,2) = 55/36 = 1.528, and C(12,2)/C(11,2) = 66/55 = 1.200.

The May 2011 change also added a second weekly draw and a new lowest tier; the September 2016 change raised the ticket price and the minimum jackpot (EuroMillions changes timeline). Current rules: EuroMillions odds.

Australian Powerball — 1 March 2013 and 19 April 2018

Era Matrix Calculation Jackpot odds
From 1996 5 of 45 + 1 of 45 1,221,759 × 45 1 in 54,979,155
From 1 March 2013 6 of 40 + 1 of 20 3,838,380 × 20 1 in 76,767,600
From 19 April 2018 7 of 35 + 1 of 20 6,724,520 × 20 1 in 134,490,400

Longer by 2.446× across the two changes. The 2018 figure matches the Division 1 odds The Lott publishes exactly, which is the cross-check we apply to every game record — see Australian Powerball odds.

Oz Lotto — 17 May 2022

From draw 1474 on 17 May 2022, Oz Lotto moved from seven numbers drawn from 45 with two supplementaries to seven from 47 with three.

Before After
Matrix 7 of 45 + 2 supps 7 of 47 + 3 supps
Division 1 combinations C(45,7) = 45,379,620 C(47,7) = 62,891,499
Overall odds of any prize 1 in 55 1 in 51

Two extra balls, and the top division becomes 1.386× harder. The third supplementary is what pays for it: adding a supplementary ball creates additional ways to win the lower divisions without touching Division 1, which is why the overall odds improved at the same time (Lotterywest — Oz Lotto update FAQs). Current rules: Oz Lotto odds.

Canada's Lotto Max

Lotto Max now draws seven numbers plus a bonus from a pool of 52. C(52,7) = 133,784,560, and because a $6 play buys four selections the operators quote the jackpot as 1 in 33,446,140 — which is 133,784,560 ÷ 4 exactly (WCLC — Lotto Max). The pool has been enlarged since the game launched; we have not found an operator source dating each step, so those dates are left out. See Lotto Max odds.

The pattern

Nine dated changes across six games. Eight lengthened the odds or raised the price per unit of jackpot chance; the ninth — Mega Millions 2025 — shortened the odds by 4% while raising the price by 150%.

Every one of them produced a larger typical advertised jackpot, and the reason that works is short enough to state in a sentence: the expected jackpot at the moment it is won is proportional to the number of combinations, and independent of how many tickets are sold. That derivation is in jackpot fatigue, and the operator-versus-player accounting of each redesign is in why lotteries changed their matrices.

To compare what any current game charges per unit of jackpot chance, use the cost-per-chance calculator or the odds calculator.

Related games

Try it yourself

Keep reading

Sources

Last verified: 2026-08-29