The Sum You're Asking About
Add together every number on a standard roulette wheel, 0 through 36, and you get 666. That total is the same on a European single-zero wheel and an American double-zero wheel, because the double zero contributes nothing to the sum. The figure is a curiosity, a piece of wheel trivia that gets repeated because of its associations. What it does not do is tell you anything about how the game pays, which bets cost you the least, or where the operator's advantage sits. Those things depend on the wheel's structure, not on the sum of its printed numbers.
What matters at the table is which pockets exist. A European wheel has 37 pockets: the numbers 1 through 36 plus a single zero. An American wheel has 38: the same 1 through 36, a single zero, and a double zero. That one extra pocket changes the arithmetic of every bet on the layout, and it is the first thing to check when you sit down.
Why the Extra Pocket Changes the Payouts
Roulette bets are priced as if the zero pockets did not exist. A straight-up bet on a single number pays 35 to 1, which would be a fair price on a wheel with 36 pockets. But the wheel has 37 or 38. The gap between the payout and the true odds is the house edge, and it is the operator's built-in advantage on every spin, regardless of which number you choose or how much you stake.
House edge and Return to Player (RTP) are complements: they sum to 100% for the same bet under the same rule set. RTP is a theoretical percentage of total wagered money a game returns to players over a very large number of spins or hands. It is a long-run statistical average, not a per-session guarantee. If a bet carries a house edge of 2.Under those rules, its RTP is a small fraction below the headline percentage.30%. Those figures describe the rate of expected loss over time, not what any single session will produce.
The double zero is the more expensive wheel for almost every bet, because it adds a losing pocket without improving any payout. The single zero is the leaner layout. Some European tables also apply a rule that returns half of certain even-money bets when the ball lands in zero; that rule changes the edge on those specific bets only, and it is printed in the table's own rule card.
How a Round Moves
A roulette round is a sequence of fixed steps, and knowing the order prevents most procedural mistakes. You buy in at the table by placing cash on the layout; the dealer exchanges it for coloured chips that are unique to you at that table. Those chips have no value away from the wheel, so you convert them back to cash chips before you leave.
Betting opens when the dealer clears the previous result and pushes the marker aside. You place chips on the layout yourself for inside bets, or announce outside bets if the table allows called bets. The dealer spins the wheel in one direction and the ball in the other. At a certain point the dealer calls no more bets, and from that moment nothing on the layout may be touched. When the ball settles, the dealer marks the winning number, clears losing bets, and pays winners in order.
Three mistakes recur. The first is reaching for your bet after the no-more-bets call; the camera and the dealer both watch for that, and it voids the round's trust. The second is leaving the table with coloured chips, which cannot be cashed at the cage. The third is placing a bet on the line between two numbers and assuming it covers both; it does, but it pays as a split bet at 17 to 1, not as two straight-ups.
Bet Types and Their Different Edges
Every bet on the layout is a separate wager with its own payout, its own probability, and often its own house edge. The distinction that matters most is between inside and outside bets, but the edge also differs between even-money outside bets and the five-number bet found only on American wheels.
| Bet | Covers | Payout | What changes the edge |
|---|---|---|---|
| Straight-up | One number | 35 to 1 | Same edge on both wheel types for this bet |
| Split | Two adjacent numbers | 17 to 1 | Same edge on both wheel types |
| Street | Three numbers in a row | 11 to 1 | Same edge on both wheel types |
| Red/black, odd/even, high/low | 18 numbers | 1 to 1 | Lower edge on single-zero wheels; some European rules return half on zero |
| Five-number (0, 00, 1, 2, 3) | Five numbers, American wheel only | 6 to 1 | Highest edge on the layout; no European equivalent |
The table shows why the wheel type matters more than the bet's name. The five-number bet is the worst wager on an American layout because its payout is priced even more generously to the house than the rest of the board. On a European wheel, the even-money bets are the leanest choices because the single zero is the only losing pocket for them, and a rule that returns half the stake on zero reduces their expected loss further.
No betting pattern changes the built-in edge of a negative-expectation game. Progression systems, such as doubling after losses, redistribute outcomes rather than remove the edge. They change the shape of your session, not the rate at which the wheel expects to keep its percentage. The only genuine controls are which bets you place, how long you play, and how much you stake per spin.
What the Wheel Layout Tells You Before You Bet
The felt layout and the wheel itself carry the information you need to answer the question for the table in front of you. The wheel's zero pockets tell you which variant you are playing. The table's rule card states whether the zero rule applies to even-money bets, what the table minimum and maximum are, and whether any side bets are offered. The payout printed beside each bet is the payout, not the true odds; the difference between the two is where the edge lives.
If you want the exact house edge for a specific bet at a specific table, the calculation is straightforward: count the losing pockets for that bet, divide by the total pockets, and subtract any rule that returns part of the stake. The article cannot state a universal percentage for every bet because the zero rule, when present, applies only to certain wagers. The wheel in front of you gives the inputs; the rule card gives the exceptions.
FAQ
Does the total of 666 have any effect on the game?
No. The sum of the printed numbers is a fixed property of the layout and has no bearing on payouts, probabilities, or the house edge. The number of pockets, not the sum of their labels, drives the arithmetic.
Is the sum different on an American wheel?
The sum of the numbers 0 through 36 is the same on both wheel types. The American wheel adds a double zero pocket, which contributes zero to the total but adds one more losing pocket to every bet.
Which roulette bet has the lowest house edge?
On a single-zero wheel, the even-money outside bets generally carry the lowest edge, and a rule returning half the stake on zero lowers it further for those bets. On a double-zero wheel, the same even-money bets are more expensive, and the five-number bet is the most expensive on the layout.
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This article is general information about how these mechanics work. It is not legal advice and not a recommendation to gamble or to use any particular operator. Availability and legality differ by jurisdiction — check the rules that apply where you are.