Single, double or triple zero: how the roulette wheel sets the house edge

Economics

A single zero gives the house 2.70% of every stake, a second zero 5.26%, and a third 7.69%.

The math behind the zeros

The number of zeros on a wheel directly dictates the mathematical advantage held by the operator. As the key figures show, a single-zero layout yields a lower edge than layouts with additional zeros. The table below lists these specific percentages for each configuration. Each extra zero adds a pocket that does not correspond to a winning number for most bets, increasing the probability of a loss relative to the payout. This structural difference is fixed and cannot be altered by player strategy. Operators select wheel types based on these inherent margins. The difference between a single-zero and a triple-zero wheel is significant for long-term profitability calculations.

House edge by roulette wheel
WheelHouse edge
Single zero2.7%
Single zero, la partage, even-money bets1.4%
Double zero5.3%
Triple zero7.7%

Impact of la partage rules

Some single-zero variants apply the la partage rule to even-money bets. This rule returns half the stake when the ball lands on zero. As the key figures show, this reduces the house edge on those specific bets to half of the standard rate. The table above confirms this lower percentage compared to the standard single-zero edge. This mechanism effectively halves the loss on zero outcomes for even-money wagers. It does not apply to other bet types. Operators offering this rule accept a lower margin on half the board to attract players who prefer lower volatility on simple bets. The calculation remains straightforward: the zero pocket’s impact is mitigated by returning part of the stake.

Operator selection criteria

Operators choose wheel configurations based on desired profit margins and player preferences. Triple-zero wheels offer the highest edge, as the table above indicates. Double-zero wheels sit between single-zero and triple-zero options. The choice affects the average cost to the player per spin. Higher edges mean faster depletion of player funds, which can influence session length and retention metrics. Regulators monitor these edges to ensure transparency in pricing. See the regulation tracker for current standards. The distinction between wheels is a primary factor in game selection for online and land-based venues. Operators balance the attractiveness of lower edges against the need for higher margins. Each configuration serves a different segment of the market based on these mathematical realities.

Questions

Why does adding zeros increase the house edge?

Each zero adds a losing outcome for most bets without increasing the payout odds proportionally. This shifts the probability balance in favor of the operator, raising the mathematical advantage with each additional pocket.

How does la partage change the edge?

It halves the loss on even-money bets when zero occurs. This reduces the overall house edge for those specific bets compared to standard rules, making them less costly for players over time.

Which wheel has the highest house edge?

The triple-zero wheel has the highest edge among common variants. The double-zero wheel follows, with the single-zero wheel offering the lowest standard edge before applying specific rules like la partage.

Every figure on this page is computed by code from standard industry formulas and the facts of our regulation tracker, each checked a second way. See the methodology.

Updated: