Three games share the name roulette, and to a casual glance they are identical: a spinning wheel, a bouncing ivory-coloured ball, a grid of red and black numbers. The differences hide in one or two pockets and a pair of French phrases, yet they are large enough that the American version costs players roughly four times as much per wager, on average, as the French one.
One zero or two
The original game that spread through Parisian gaming houses in the 1790s carried both a zero and a double zero, which belonged to the house. The single-zero wheel was a marketing invention. In 1843 the brothers François and Louis Blanc, running the casino at Bad Homburg in Germany, deleted the double zero to undercut their competitors’ odds and draw players away from other spa towns. When Louis Blanc later took over the concession at Monte Carlo in the 1860s, the single-zero wheel went with him and became the European standard. The double-zero wheel, meanwhile, sailed to America, where it survived and eventually acquired the American name despite being the older French design.
The arithmetic follows directly. A European wheel has 37 pockets, so a single-number bet paying 35 to 1 gives the house an edge of 2.70 per cent. An American wheel has 38 pockets with the same 35 to 1 payout, producing an edge of 5.26 per cent on nearly every bet. One American wager is worse still: the five-number basket covering 0, 00, 1, 2 and 3 carries a 7.89 per cent edge, the poorest standard bet on the layout.
What makes French roulette French
French roulette uses the same 37-pocket wheel as the European game and adds player-friendly rules on even-money bets such as red or black. Under la partage, a ball landing on zero returns half of any even-money stake. Under en prison, the stake is instead held captive for the next spin and returned in full if that bet then wins. Either rule cuts the house edge on even-money wagers to 1.35 per cent, the lowest figure in mainstream roulette. French tables also traditionally use the announced call bets tied to the wheel’s physical layout, voisins du zéro, tiers du cylindre and orphelins, placed via the oval racetrack diagram. The wheels differ in sequence too: European and French wheels share one number ordering, while the American wheel arranges numbers so that consecutive values sit opposite each other, though the sequence has no effect on the odds.
Where each version lives
Geography still largely follows the Blanc brothers’ commercial map. Single-zero tables dominate Europe, the United Kingdom and most of Asia; double-zero tables dominate the United States, although Las Vegas casinos do offer single-zero games, historically in higher-limit rooms. Online casinos scrambled the map entirely, since a platform can host every variant side by side at no extra cost, with outcomes driven by certified random number generators or live-streamed physical wheels, as described in this magazine’s guide to how online casinos work. A notable recent twist runs in the opposite direction: triple-zero wheels, carrying a 7.69 per cent edge, have spread across the Las Vegas Strip since first appearing there in the 2010s. Roulette’s wider family of variants and table games is covered in the magazine’s casino section.
The comparison in brief
Expressed as expected cost, the differences are stark. Over 100 spins at 10 units per spin, a player faces an average theoretical loss of about 13.50 units at a French table with la partage on even-money bets, 27 units at a European table, and nearly 53 units at an American double-zero table. No bet selection or staking pattern alters those figures, because every roulette bet on a given wheel, with the American basket bet as the lone exception, carries the same edge. The game’s mathematics were settled long ago; the only genuine variable left is which wheel is spinning.