# What is the Casino House Edge?

Published Date · Oct. 16, 2020 · Last Updated · Aug. 14, 2024 ·Read Time · 16 mins

When you step into a casino, whether online or in person, the thrill of potential wins is always palpable. However, underlying every game is a critical concept known as the house edge. This term represents the mathematical advantage that casinos have over players, ensuring their long-term profitability.

Understanding this concept is essential for anyone who gambles, as it directly impacts how much players can expect to win or lose over time. This article will break down what the house advantage is, how it's calculated, and its significance in different casino games, including slots, roulette, and blackjack. We'll also explore how it compares to the return to player (RTP) metric, its role in sports betting and poker, and why it's a crucial factor in gambling. Additionally, we'll discuss strategies to minimize this advantage and debunk common myths about it.

## What is the House Edge?

It's a term used in gambling to describe the mathematical advantage that the casino has over the players in any given game. It represents the percentage of each bet that the casino expects to keep as profit over the long run. For example, if a game has a house edge of 5%, the casino expects to make \$5 for every \$100 wagered on that game.

### Why Does the House Edge Exist?

This advantage exists to ensure that casinos remain profitable over time. Every game is designed with specific rules and odds that favor the casino, meaning that while players may win in the short term, the casino will always win in the long term. This is not due to any manipulation or unfair practices, but rather a result of the statistical nature of the games.

### Example of House Advantage in Action

• Consider a simple example in the game of roulette. In American roulette, there are 38 pockets (1-36, 0, and 00). If you bet on a single number, the payout is 35 to 1. However, since there are 38 possible outcomes, the true odds of winning are 37 to 1. The difference between the true odds and the payout odds represents the house edge, which in American roulette is approximately 5.26%.

## Origins and Concept of House Edge

### Historical Background

The concept of the house edge originated in the earliest forms of gambling, where games were designed to guarantee that the operator would make a profit over time. As gambling became more organized and widespread, especially with the rise of casinos in places like Monte Carlo and Las Vegas, this advantage became a crucial element in the design of casino games. This mathematical principle ensures that, despite short-term player wins, the casino will ultimately retain a percentage of all wagers in the long run.

### The Mathematical Basis

The house edge is rooted in probability and statistics. It arises because the payouts for winning bets are always set slightly below the true odds of winning. This discrepancy between the actual odds of a game and the payout odds is what creates the advantage .

• In a fair coin toss, there are two possible outcomes: heads or tails, with each having a 50% chance. If a bet on either outcome paid 1:1, there would be no house edge, and the game would be fair. However, if the payout was reduced slightly to 0.95:1, the operator would introduce an advantage , ensuring a profit over many plays.

### Evolution of the Concept

Over time, the house edge has evolved to adapt to new games and gambling formats, including online casinos, where algorithms and software are designed to maintain the same principles. This advantage has also been applied beyond traditional casino games to include sports betting, lotteries, and other forms of gambling, ensuring that operators consistently profit while still providing players with a chance to win.

## How is House Edge Calculated?

### The Basic Formula

It's calculated by determining the difference between the true odds of winning a bet and the payout odds offered by the casino. The basic formula is:

This formula gives the house edge as a percentage, representing the average amount of each bet that the casino expects to keep over the long term.

### Examples by Games :

#### Roulette

Consider the game of American Roulette, which has 38 pockets (numbers 1-36, 0, and 00). If you place a bet on a single number, the payout is 35 to 1. However, the true odds of hitting that single number are 37 to 1, since there are 37 ways to lose and only 1 way to win.

Using the formula:

This means that, on average, the casino expects to keep 5.26% of all money wagered on single-number bets in American Roulette.

#### Blackjack

In Blackjack, the advantage varies depending on the player's strategy and the specific rules of the game. For instance, if a player follows basic strategy (a set of mathematically optimal moves), the blackjack house edge can be reduced to around 0.5%. The advantage here is calculated by considering the probability of all possible outcomes (wins, losses, ties) and the payouts for each, factoring in the player's optimal decisions.

#### Slots

Slot machines typically have a higher house edge, which can range from 2% to 15%, depending on the game. The calculation in slots is more complex and involves the design of the game itself, including the probability of landing winning combinations and the payouts for those combinations. Slot developers build these probabilities into the game's software to ensure that over many spins, the machine will return a certain percentage to the casino.

## House Edge Vs RTP (Return to Player)

### What is RTP ?

It's a key metric in gambling that represents the percentage of all wagered money a game is expected to return to players over time. Unlike the house edge, which focuses on the casino’s advantage, RTP is expressed from the player's perspective. For example, if a slot machine has an RTP of 96%, it means that, on average, for every \$100 wagered, the game will return \$96 to players and keep \$4 as profit for the casino.

### Relationship Between House Edge and RTP

The house edge and RTP are two sides of the same coin. They are directly related and together add up to 100%. The formula to derive one from the other is straightforward:

For instance, if a game has an house advantage of 5%, the RTP would be:

This means that over time, the game will return 95% of all wagers to players, with the remaining 5% being the casino's profit.

### Importance of RTP in Casino Games

RTP is particularly important in games like slots, where players have little control over the outcome. Since the game is purely based on chance, knowing the RTP can help players choose machines that offer better long-term returns. Higher RTPs are generally more favorable to players, as they reduce the casino’s profit margin and increase the amount of money returned to players over time.

### House Edge vs. RTP in Different Casino Games

• Slots: Slot machines typically have RTPs ranging from 85% to 98%, depending on the game. A slot with a 95% RTP has a house edge of 5%, meaning the casino expects to keep 5% of all money wagered on that machine.
• Table Games: In games like roulette or blackjack, the house edge and RTP are directly influenced by the rules of the game and the player’s strategy. For example, European Roulette has a lower advantage (2.7%) compared to American Roulette (5.26%), leading to higher RTPs for the European version.

### Why Both Metrics Matter

Understanding both house edge and RTP is essential for players who want to make informed decisions about which games to play. While the house advantage gives insight into how much the casino expects to earn from a game, RTP shows players how much they can expect to win back over time. Games with lower house edges (and therefore higher RTPs) are generally more favorable to players, especially those looking to maximize their long-term chances of winning.

## House Edge of Various Casino Games

This advantage varies significantly across different casino games, reflecting the inherent risks and probabilities involved in each game.

Casino Game
House Edge (Approximate)
Description

Slots

2% to 15%
The House Edge in slots varies, with simpler games having lower edges.

European Roulette

2.7%

European Roulette has a favorable 2.7% edge due to its single zero.

American Roulette

5.26%
American Roulette’s double zero increases its House Edge.

Blackjack

0.5% to 2% (with basic strategy)
In Blackjack, good strategy keeps the edge low, but poor play raises it.

Baccarat

1.06% (Banker bet), 1.24% (Player bet), 14.36% (Tie bet)

Baccarat’s Banker bet has a low edge; the Tie bet has a high edge.

Craps

1.36% (Pass Line bet)
Craps has low edges on bets like Pass Line, but some bets exceed 10%.

Keno

25% to 29%
Keno has a high House Edge, making it less appealing.

Video Poker

0.5% to 5%
Video Poker’s edge varies, with some games offering low edges with optimal play.

### Casino Games with the Lowest House Edge

• Blackjack (0.5% with basic strategy): With perfect play and adherence to optimal strategy, blackjack can offer one of the lowest house edges, making it highly favorable for skilled players.
• Baccarat (1.06% on Banker bet): The Banker bet in Baccarat has a very low house edge, making it one of the best bets in the casino. The Player bet is slightly less favorable at 1.24%, but still offers good odds. However, the Tie bet should be avoided due to its high house advantage.
• Craps (1.36% on Pass Line bet): Craps is popular for its low House Edge on basic bets like the Pass Line. Players can reduce the house edge further by taking odds bets.

### Casino Games with the Highest House Edge

• Keno (25% to 29%): Keno is one of the riskiest casino games, with an extremely high house edge. While the potential payouts can be large, the odds of winning are very low.
• Slot Machines (2% to 15%): While the house advantage varies across different machines, some slots—especially those with complex bonus features—can have a very high house edge.
• American Roulette (5.26%): Due to the presence of both 0 and 00 pockets, American Roulette gives the casino a significant advantage compared to European Roulette.

## House Advantage in Sports Betting

Sports betting, like casino games, also incorporates a house edge to ensure that bookmakers remain profitable over time. However, the way it's applied in sports betting differs significantly from traditional casino games.

### How House Edge is Applied in Sports Betting

In sports betting, the house edge is built into the odds offered by bookmakers, who adjust the odds slightly in their favor to ensure a profit margin, known as the "vig" or "juice."

• For instance, in a two-outcome bet where the true odds suggest a 50% chance for each side, the bookmaker might offer slightly lower odds, like 1.91 instead of 2.00, to create a built-in advantage.

The advantage in sports betting is calculated using the following formula:

Where the total implied probability is the sum of the implied probabilities of all possible outcomes based on the odds offered. The higher the total implied probability exceeds 100%, the greater the house edge.

### Differences Between Casino and Sports Betting

• Nature of Probability: In casino games, probabilities are fixed and well-defined, making the house advantage clear and consistent. In sports betting, probabilities are estimated and influenced by unpredictable factors like injuries or weather, making outcomes less certain.
• Market Influence: Casino games have a fixed house edge determined by game rules, while sports betting odds can fluctuate based on market conditions, such as betting patterns and external events, dynamically affecting the house advantage.
• Player Skill and Information: In sports betting, bettors can reduce the bookmaker's advantage through skill and research, potentially even gaining an edge. In contrast, overcoming the house advantage in casino games through skill is much more difficult.

## House Edge in Poker

Poker is unique among casino games because it doesn't have a traditional house advantage. Instead of competing against the house, players compete against each other, with the casino earning its profit through a system called the "rake."

### How Poker Differs from Other Casino Games

In most casino games, the house edge ensures the casino will profit over time by maintaining a statistical advantage on every bet. However, poker is different; it’s a game of skill and strategy where players compete against each other, not the house. This means the outcome depends on the players' decisions and abilities, so the casino doesn't need a traditional House Edge in poker.

### The Concept of the Rake and Its Impact on Players' Winnings

Casinos profit from poker not through a traditional house edge, but by taking a small percentage of the pot in each hand, known as the "rake". Typically, this rake ranges from 2.5% to 10%, with a cap on how much can be taken. For instance, in a \$100 pot with a 5% rake, the casino takes \$5. While this ensures steady income for the casino, it reduces players' overall winnings, especially over many hands. To mitigate this, skilled players often seek games with lower rake percentages or caps and may benefit from "rakeback" programs that return a portion of the rake.

## Why is the House Edge Important?

Understanding the concept is crucial for anyone who engages in casino gambling, as it has a direct impact on how much money players can expect to win or lose over time. This advantage ensures that, in the long run, the casino will make a profit, which inevitably affects the players' overall outcomes.

### Players Lose More Than They Win

The house advantage guarantees that, statistically, players will lose more money than they win over an extended period. This is because the odds of winning are always slightly less favorable than the payouts suggest.

• For example, in a game like American Roulette, the presence of the 0 and 00 pockets means that players have less than a 50% chance of winning even money bets, yet those bets still pay out at 1:1. Over time, this mathematical imbalance ensures that the casino gradually accumulates more money than it pays out, leading to a net loss for players.

Even though players may experience short-term wins, the house edge ensures that these are usually outweighed by the inevitable losses, especially as the number of bets increases. This statistical inevitability is why casinos remain profitable despite the occasional big win by a player.

### Impact on Long-Term Winnings

For players who gamble regularly, understanding the house edge is essential for grasping the long-term implications of their gaming activities. This advantage not only dictates how much money the casino will keep from all bets made but also serves as a predictor of how much a player can expect to lose over time.

• For instance, a game with a 5% House Edge means that, on average, a player will lose \$5 for every \$100 wagered over the long term. By understanding this, players can better assess their expected losses and plan their gambling activities accordingly. This knowledge helps in setting realistic expectations and avoiding the common pitfall of believing that frequent wins will lead to long-term profit.

### Role in Bankroll Management

Effective bankroll management is a key aspect of responsible gambling, and knowledge of the house edge plays a vital role in this.

• For example, if a player knows that a particular game has a high house adavantage, they might choose to limit their time spent on that game or adjust their bet size to manage potential losses better. Conversely, a game with a lower might be a better option for extended play, as the expected losses per bet are smaller.

Additionally, understanding this concept can help players determine the appropriate size of their bankroll. By knowing how much they are likely to lose over time, players can set aside a bankroll that allows them to enjoy their gambling activities without risking more money than they can afford to lose.

## How to Minimize House Advantage

• Smart Betting Strategies: Using optimal strategies can significantly reduce the house advantage in certain games. For example, in Blackjack, following basic strategy can lower the house edge to around 0.5%. In craps, sticking to bets with the lowest House Edge, like the Pass Line bet, can also help minimize losses.
• Choosing Games with Lower House Edge: Selecting games with a naturally lower house advantage is one of the most effective ways to reduce losses. Games like Baccarat (Banker bet with a 1.06% edge), Blackjack (with basic strategy), and European Roulette (2.7% edge) offer better odds compared to games like Keno or American Roulette.
• Importance of Understanding Game Rules and Strategies: Thoroughly understanding the rules and strategies of a game is crucial for minimizing the house edge. In games like Baccarat, knowing the correct strategy can reduce the casino advantage. Mastering the rules and optimal play techniques ensures you don't give the house an unnecessary advantage.

## Debunking Common House Edge Myths

This concept is often misunderstood, leading to several myths that can misguide players. Here’s a look at some common misconceptions and the reality behind them.

#### Myth 1: "The Casino Always Wins Because the Games Are Rigged"

• Reality: The games aren’t rigged in the traditional sense; they are designed with a built-in mathematical advantage, known as the house advantage. This ensures the casino profits over the long run, but it doesn't mean players can't win. Short-term wins are possible, and some players can and do walk away with substantial winnings. The advantage simply means that, over time, the odds favor the casino, not the player.

#### Myth 2: "You Can Beat the House Edge with a Betting System"

• Reality: No betting system can overcome the house edge. Systems like the Martingale, which involves doubling bets after losses, are popular but ultimately ineffective. These systems rely on the assumption of unlimited funds and no betting limits, which isn’t realistic. The house advantage persists regardless of the betting strategy because it’s built into the game’s odds.

#### Myth 3: "Games with Higher Payouts Have a Lower House Edge"

• Reality: High payouts do not necessarily mean a lower house edge. For example, slot machines with large jackpots often have a higher than those with smaller payouts. The payout size is attractive, but the odds of winning are typically lower, leading to a higher overall house edge.

#### Myth 4: "The Longer You Play, the More Likely You Are to Win"

• Reality: The opposite is true. The longer you play, the more the house edge works against you. Over time, the statistical advantage of the casino will erode any short-term winnings. That’s why it’s often better to play for shorter periods and cash out after a win rather than continuing to play in the hope of further gains.

#### Myth 5: "The House Edge Can Be Overcome with Skill"

• Reality: While skill can reduce the house edge in certain games, like Blackjack or Video Poker, it cannot eliminate it entirely. Even the best players face a house edge, albeit a much smaller one. For games of pure chance, like roulette or slots, no amount of skill can overcome it.

## Final Advice

It's a fundamental concept that every casino player should understand. It’s the mathematical advantage that ensures casinos remain profitable over time, but it doesn’t mean that players can’t win. By understanding how the house advantage works across different games, players can make more informed choices, select games with better odds, and employ strategies to minimize losses.

Whether you’re playing poker, betting on sports, or trying your luck at the slots, knowing the concept helps you manage your expectations and your bankroll. It reminds us that while gambling can be a fun and exciting activity, it’s essential to play responsibly, with a clear understanding of the odds.

Ultimately, knowledge of the house advantage empowers players to enjoy their casino experience more fully, making the thrill of the game just a bit more calculated—and a lot more informed.

Author

Phoebe Greenwood

Content Writer