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House edge explained: the price of every casino bet
House edge is the share of each stake a casino keeps on average. See how it is calculated, how it relates to RTP and what it costs per hour of play.
- House edge is the average share of each bet the casino keeps over the long run. A 2.70% edge means an expected loss of $2.70 per $100 staked.
- RTP is the same figure seen from the player’s side: RTP = 100% minus house edge.
- What a session costs depends on the edge, the stake and the number of bets per hour, so a fast game with a small edge can cost more than a slow game with a large one.
What house edge measures
Every casino bet pays slightly less than the true odds of winning it. The gap is the house edge, written as a percentage of the stake. On a single-zero roulette wheel a straight-up number wins once in 37 spins but pays 35 to 1, so over 37 one-dollar bets you get back $36 on average. The missing dollar, 1/37 or 2.70%, is the edge.
The figure is an average over a very large number of bets. In a single evening results swing far above and below it. The edge tells you the direction and the size of the long-run drift, not what will happen tonight.
House edge and RTP are the same number
Slots and other machine games usually publish a return to player (RTP) percentage instead. A slot with a 96% RTP has a 4% house edge. Table games are normally described by edge and slots by RTP, but you can convert either way by subtracting from 100. Our explainer on RTP covers how the figure is tested and monitored.
How the edge compares across common bets
| Bet | House edge | Expected loss per $100 staked |
|---|---|---|
| Blackjack, basic strategy, 3:2 payout | about 0.5% | $0.50 |
| Baccarat, banker | 1.06% | $1.06 |
| Baccarat, player | 1.24% | $1.24 |
| Craps, pass line | 1.41% | $1.41 |
| European roulette, any bet | 2.70% | $2.70 |
| Online slot with 96% RTP | 4.00% | $4.00 |
| American roulette, most bets | 5.26% | $5.26 |
| Baccarat, tie paid 8 to 1 | 14.36% | $14.36 |
The blackjack figure assumes correct basic strategy and favourable rules; see which blackjack rules change the edge. The roulette figures come straight from the number of pockets, explained in roulette odds and payouts.
Working out what an hour costs
Expected loss per hour = average stake × bets per hour × house edge. The middle term matters as much as the last one.
| Game | Stake | Bets per hour | Edge | Expected loss per hour |
|---|---|---|---|---|
| European roulette | $10 | 40 | 2.70% | $10.80 |
| Blackjack, basic strategy | $10 | 70 | 0.5% | $3.50 |
| Online slot, 96% RTP | $1 | 600 | 4.00% | $24.00 |
The slot has the smallest stake in the table and the highest hourly cost, because it is played fifteen times faster than roulette. Speeds are illustrative; the arithmetic is what carries over.
What house edge does not tell you
- It says nothing about variance. Two games with the same edge can feel completely different; that is what volatility describes.
- It cannot be removed by a staking pattern. Changing bet sizes changes how results are distributed, not the average. See roulette strategy.
- It applies to money staked, not money brought. Winnings that are bet again are exposed to the edge again, which is why bankrolls shrink faster than the percentage suggests.
Common questions
Is a lower house edge always better?
For the cost of play, yes: a lower edge means a smaller expected loss per dollar staked. Total cost also depends on stake size and how many bets you make per hour.
What is the difference between house edge and RTP?
They describe the same thing from opposite sides. RTP is the share of stakes returned to players over the long run; house edge is the share kept. They add up to 100%.
Which casino game has the lowest house edge?
Among common games, blackjack played with basic strategy on a 3:2 table (about 0.5%) and full-pay Jacks or Better video poker (about 0.46% with optimal play) are the lowest. Both depend on the exact rules and on playing correctly.
Sources
Checked 11 November 2026. Rules and published figures change; confirm against the current official page before relying on them.
Publication byline. Prepared with AI assistance and checked against the linked sources; see our editorial standards. This page is information, not advice, and contains no affiliate links.