American vs. European Roulette: The One Extra Pocket That Nearly Doubles the House Edge

Two roulette wheels sit side by side in most casinos today, but only one hides an extra pocket that shifts the odds. The American wheel carries a second green pocket marked 00, while the European wheel keeps a single zero. That one extra number looks small on a wheel with thirty-seven or thirty-eight slots, yet it changes the math behind every spin at the table. Regular players who understand this difference often plan their sessions around it, choosing tables that give them a better shot at walking away ahead.

The Physical Difference Between the Two Wheels

An American wheel has thirty-eight pockets numbered 1 through 36, plus a single 0 and a double 00. A European wheel drops that second zero, leaving thirty-seven pockets in total. The extra pocket does not change how the game plays out on the felt: bets, chip placement, and payout amounts all work the same way at both tables. What changes is the probability of the ball landing on any single number, since the same payout now gets split across one more possible outcome on the American wheel.

Spotting the difference before sitting down saves confusion once chips are already on the table. A quick glance at the number ring under the dealer’s rack shows if a second green pocket is present, which is usually the fastest way to tell the two wheels apart. Newcomers who want to try online casino roulette gamesat TheOnlineCasino or any other platform they’re new to should look for a single zero if they want better odds. 

Where the Second Zero Sits

On the American wheel, the 00 pocket sits directly across from the single 0, splitting the two green numbers onto opposite sides of the layout. This placement breaks up the number sequence that dealers and regular players use to judge roughly where a ball might land after a run of spins. Historians of the game generally trace the double zero to American operators in the 1800s, who added the pocket to widen their edge after the single zero wheel had already spread through European casinos.

Why One Pocket Moves the House Edge So Much

House edge comes from comparing the true odds of a bet against what the casino actually pays out. A straight bet on a single number pays 35 to 1 on both wheels. On a European wheel, the true odds against hitting that number are 36 to 1, so the casino keeps a modest cut. 

On an American wheel, the true odds stretch to 37 to 1 because of the extra pocket, while the payout stays exactly the same. That one additional losing outcome, spread across every bet on the table, is where nearly all of the gap between the two wheels comes from.

The gap shows up clearly once the numbers are lined up side by side:

● American double zero wheel: Standard inside and outside bets carry a house edge of about 5.26 percent.

● American five number bet: The bet covering 0, 00, 1, 2, and 3 carries a house edge near 7.89 percent, the worst on either wheel.

● European single zero wheel: Straight bets and even money bets carry a house edge of about 2.70 percent.

● French roulette with La Partage: Even money bets that lose to zero return half the stake, cutting the edge to roughly 1.35 percent.

Lined up this way, the difference between wheels amounts to more than double the cost of play over a long session, even though the layout on the felt looks almost the same.

The Five Number Bet Trap

The five number bet only exists on the American wheel, since it depends on having both zeros sitting next to the first three numbers on the layout. Every other bet keeps its house edge at 5.26 percent because the payout is calculated as if the wheel had only 36 numbers, with the two zero pockets simply left uncovered. 

The five number bet works differently: it covers all five numbers, zeros included, yet still pays out at only 6 to 1, when a payout matching the true odds would need to be closer to 6.6 to 1. That shortfall between fair odds and the rounded-down payout is what pushes the house edge on this one bet to 7.89 percent, well above the 5.26 percent found everywhere else on the same wheel. 

European Variants That Cut the Edge Further

Some European tables add rules that lower the house edge even more. Under La Partage, a player loses only half their stake when the ball lands on zero during an even-money bet like red, black, odd, or even. 

Another bet, En Prison, works in a similar way but leaves the bet on the table for another spin instead of returning half of it right away. 

Both rules cut the standard European edge of 2.70 percent roughly in half, landing near 1.35 percent for the bets they cover, and both show up mostly in French-style games and a smaller set of European casinos.

Final Word on What This Means at the Table

Wheel choice matters more than any betting system a player might bring along, since no pattern of bets changes the built-in odds of either wheel. Given a choice between an American and a European table with similar minimums and similar company, picking the wheel with one zero instead of two adds up over a full session. That single pocket, small as it looks, remains the clearest factor distinguishing a good session from a costly one at the roulette table.