House Edge
The casino's built-in average profit on a game, shown as a percentage of each bet.
The house edge is the casino's mathematical advantage on a game. It is the percentage of each bet the casino expects to keep over the long run. A game with a 5% house edge returns, on average, $95 for every $100 bet.
It doesn't tell you what will happen in one session. It tells you what happens over thousands of bets.
House Edge on Common Casino Games
| Game / Bet | House Edge |
|---|---|
| Blackjack (basic strategy, good rules) | about 0.5% |
| Baccarat, banker bet | 1.06% |
| Baccarat, player bet | 1.24% |
| Craps, pass line | 1.41% |
| European roulette (single zero) | 2.70% |
| American roulette (double zero) | 5.26% |
| Slot machines | varies widely, often 2% to 15% |
| Baccarat, tie bet (8 to 1) | 14.36% |
| Keno | often 20% to 35% |
How the House Edge Affects You
Multiply the house edge by your total amount bet (your "action") to get your expected loss.
100 spins of $10 on American roulette = $1,000 in action
$1,000 × 5.26% = about $52.60 expected loss
The same play on European roulette: about $27
Notice it is based on the total amount you bet, not the money you brought. Playing faster or for longer increases your expected loss even if your bet size stays the same.
Where the Edge Comes From
The casino pays a little less than the true odds. In American roulette there are 38 pockets, so a bet on one number has a 1 in 38 chance, but it pays 35 to 1 instead of 37 to 1. That gap is the house edge.
House Edge vs. RTP
RTP (return to player) is the flip side of the house edge. A slot with 96% RTP has a 4% house edge. Casinos usually talk about RTP for slots and house edge for table games.
Can You Beat the House Edge?
In most games, no. Betting systems like the Martingale don't change the edge. Blackjack is the main exception, where card counting can shift the edge to the player, though casinos watch for it and can ask counters to leave.
Key Takeaways
- The house edge is the casino's average profit as a percentage of each bet.
- Expected loss = total amount bet × house edge.
- Blackjack with basic strategy (about 0.5%) and baccarat banker (1.06%) are among the lowest edges.
- Betting systems don't change the house edge.
Examples
- $500 in total slot spins at a 6% house edge means an expected loss of about $30.
- A single-number roulette bet pays 35 to 1, but the true odds on an American wheel are 37 to 1.
Test Your Knowledge
1 / 5Do you know what RTP (Return to Player) means?
The percentage of all money bet on a game that it pays back to players over time.
Frequently Asked Questions
Which casino game has the lowest house edge?
Blackjack with basic strategy and good rules, at roughly 0.5%. Baccarat banker (1.06%) and craps pass line (1.41%) are also low.
Does the house edge mean I will lose that exact amount?
No. It is the long-run average. In a single session you can win or lose much more than the house edge suggests.