What is the difference between a single-zero and double-zero roulette wheel in terms of how the game plays?

One extra pocket on a wheel — that's really all separates these two versions of roulette. But that single pocket has a measurable, permanent effect on how much of your money the house keeps over time.

The wheel layouts

The core distinction is straightforward: European roulette features a single zero, while American roulette features both a zero and a double zero (00). Everything else about the game — the numbered pockets 1–36, the red/black split, the betting layout, the payouts — is essentially identical. Because of that one extra slot, the odds of hitting any single number on a European wheel are 1 in 37, compared to 1 in 38 on the American version.

Why the extra zero matters so much mathematically

The payouts don't change between versions. A straight-up single-number bet pays 35:1 on both wheels. The gap between that payout and the true odds is exactly where the house edge lives.

On a double-zero wheel, the true odds of hitting a single number are 37 to 1 (38 pockets), but the bet pays only 35 to 1 — and that gap, caused by both the 0 and 00, is where the house gets its edge.

The difference of one number might not seem like much, but it significantly lowers the house edge: 2.7% on European (single-zero) versus 5.26% on American (double-zero) roulette. That's nearly double the house edge on the American wheel. Statistically, that's a better deal for the player over the long term — though the change to the house edge doesn't affect the outcome of any individual bet.

The one bet that's uniquely bad on a double-zero wheel

The "Top Line" or 5-number bet — covering 00, 0, 1, 2, and 3 — exists only on the American wheel and pays 6:1. That's less than its true odds, pushing the house edge on that specific bet to 7.29%, well above American roulette's already-high average of 5.26%. It's the single worst bet on the table and has no equivalent on a single-zero wheel.

In Ontario's regulated online market

Both variants are available on licensed Ontario platforms. European (single-zero) roulette is the version to look for if the house edge matters to you — and on most sites you'll find both clearly labelled. When you're choosing where to play, make sure the site displays both the iGaming Ontario and BetGuard logos; that's your confirmation it's a fully regulated operator. The complete list of registered operators is at the iGaming Ontario website.

One practical note: house edge and RTP are averaged across all players and don't determine a single player's likelihood of winning on a specific bet or session — so the 2.7% vs. 5.26% figures describe long-run mathematical expectations, not what happens on any given spin. If you ever want to talk to someone about your play, ConnexOntario is available at 1-866-531-2600. Ontario gambling is 19+.