House Edge

The average amount a player can expect to win or lose per bet over the long run. Calculated as (probability of winning × win amount) - (probability of losing × loss amount). A positive EV means the bet is profitable long-term; negative EV means it loses money.

The percentage of wagered money that a game returns to players over time. RTP = 100% - House Edge. A slot with 96% RTP has a 4% house edge. Higher RTP means better odds for the player.

The number of times you must bet a bonus amount before you can withdraw winnings. A 30× wagering requirement on a $100 bonus means you must place $3,000 in total bets. Also called playthrough requirement.

The mathematically optimal play for every possible hand combination in blackjack, determined by computer simulation. Following basic strategy reduces the house edge to approximately 0.5%. It covers when to hit, stand, double, split, and surrender.

A roulette variant with 37 numbers (0-36) and a house edge of 2.7%. Has a single zero pocket, unlike American roulette which has two. Always choose European over American roulette for better odds.

A roulette variant with 38 numbers (0, 00, 1-36) and a house edge of 5.26%. The extra double-zero pocket nearly doubles the house edge compared to European roulette. Mathematically inferior for the player.

An additional bet placed behind the pass line after a point is established. The only bet in the casino with ZERO house edge, paying at true odds. Casinos limit odds bets (commonly 3x-4x-5x). Always take maximum odds.

The mistaken belief that past random events affect future outcomes. For example, thinking that after 10 red results in roulette, black is 'due.' Each spin is independent and the wheel has no memory. One of the most common cognitive biases in gambling.

The likelihood of a specific outcome occurring, expressed as a number between 0 and 1 (or 0% and 100%). In a fair coin flip, the probability of heads is 0.5. Understanding probability is fundamental to evaluating any casino bet.

The mathematical advantage expressed as a percentage. A player edge means positive expected value; a house edge means negative expected value. Even a small edge (1-2%) becomes significant over thousands of bets.

The actual mathematical probability of an event, expressed as a ratio. For example, the true odds of rolling a 7 with two dice are 5:1. When a casino pays less than true odds, the difference is the house edge.

The specific rules set by a particular casino that may differ from standard rules. House rules in blackjack (such as dealer hits soft 17, number of decks, doubling restrictions) significantly affect the house edge.

The amount of money paid to a winning player. Payouts are expressed as ratios (3:2, 2:1) or multipliers (35x). The difference between true odds and payout odds is where the house edge comes from.

The commission or fee charged by the house. In sports betting, the standard vig is 10% on losing bets (the -110 line). In baccarat, a 5% commission is charged on winning banker bets. Also called juice.

Software that generates random outcomes in online casino games. Certified RNGs are tested by independent auditors (eCOGRA, iTech Labs) to ensure fairness. Every spin, card deal, and dice roll in online casinos uses an RNG.

A blackjack variant that pays 6:5 instead of the standard 3:2 for a natural blackjack. This single rule change increases the house edge by about 1.4%. Always avoid 6:5 tables because they are significantly worse for players.

An optional additional wager in table games, separate from the main bet. Common blackjack side bets include Perfect Pairs, 21+3, and Insurance. Side bets almost always have a much higher house edge (2-10%+) than the main game.

A roulette bet on a single number. Pays 35:1 but has a probability of 2.7% (European) or 2.6% (American). Despite the high payout, the house edge is the same as any other roulette bet (2.7% European, 5.26% American).

A one-roll craps bet that the next roll will be a 7. Pays 4:1 but the true odds are 5:1, giving it a massive house edge of 16.67%, one of the worst bets in the entire casino.

The 5% fee charged on winning banker bets in traditional baccarat. Despite this commission, the banker bet (1.06% house edge) remains better than the player bet (1.24%). Commission-free variants exist but adjust payouts instead.

The commission charged by sportsbooks on losing bets. Standard juice is 10% (implied by the -110 line). A $110 bet at -110 wins $100 or loses $110. The juice ensures the book profits regardless of the outcome.

Another term for house edge. The built-in mathematical advantage that ensures casinos profit over time. Every casino game has a house advantage, ranging from under 0.5% (blackjack with basic strategy) to over 25% (some keno bets).

The green pocket numbered 0 on the roulette wheel. Zero gives the house its edge because even-money bets (red/black) lose on zero. European roulette has one zero (2.7% edge); American roulette adds a double zero (5.26% edge).

A rule specifying whether the dealer must hit or stand on soft 17 (Ace + 6). If the dealer hits soft 17 (H17), the house edge increases by about 0.2% compared to standing on soft 17 (S17). Always look for S17 tables.

Surrender option available before the dealer checks for blackjack. Much more valuable than late surrender and reduces the house edge by about 0.6%. Extremely rare in modern casinos because of how advantageous it is for players.