What Is the House Edge?
The house edge is the mathematical advantage a casino has built into every game it offers. It is the percentage of each bet the casino expects to keep over the long run. If a game has a 4% house edge, the casino expects to pocket $4 from every $100 wagered across millions of bets.
It is simply the flip side of RTP. A game with 96% RTP has a 4% house edge. The two numbers always add up to 100%.
Why the house always wins eventually
No casino offers a game where the expected return is higher than what you put in. Every game has a negative expected value for the player in the long run. That is not fraud — it is how the industry sustains itself. The randomness of each bet means players can win on any given session. But the more you play, the more the law of large numbers pulls actual results toward the house edge.
Professional gamblers know this. They either find games with tiny edges (blackjack with basic strategy: 0.5%), use promotional bonuses to shift the maths in their favour temporarily, or they simply accept the entertainment cost and set a budget accordingly.
House edge by game type
- Blackjack (basic strategy): 0.5%
- Baccarat (banker bet): 1.06%
- European roulette: 2.7%
- American roulette: 5.26%
- Video poker (full pay Jacks or Better): 0.46%
- Online slots: 2% to 8% depending on the game
- Keno: 20% to 35%
Blackjack played correctly has the lowest house edge of any standard casino game. The catch is that you need to learn and apply basic strategy consistently — every deviation from optimal play increases the edge you hand to the casino.
Does the house edge change during your session?
The house edge is a fixed mathematical property of the game. It does not change because you are on a winning streak. The RNG has no memory. Each spin of a slot, each hand of blackjack, each roulette spin is independent of what came before. The notion that a machine is “due” for a win is the gambler’s fallacy — a common misconception that the math simply does not support.
How casinos use the house edge
The house edge is a long-run average across all players. On any individual bet the outcome is binary — you win or you lose. But averaged across thousands of players placing thousands of bets, the casino’s income becomes predictable. This is why casinos can afford to offer welcome bonuses: the cost of the bonus is factored against the projected long-run revenue the player will generate.
Can you beat the house edge?
Not consistently over a large sample. You can reduce the edge by choosing games like blackjack with basic strategy, but you cannot eliminate it. Bonus hunters sometimes gain a short-term edge by claiming generous promotions, though casinos limit or close accounts that do this systematically.
What is the house edge on slots?
Online slots typically carry a house edge between 2% and 8%. Land-based slots often run lower RTPs, sometimes as low as 85%, giving them a house edge above 15%.
Is house edge the same as commission?
Not exactly. Commission refers to a direct fee charged on certain bets, like the 5% on banker bets in baccarat. The house edge is the broader mathematical advantage built into the game rules themselves.