RTP and House Edge Explained

This guide covers RTP and house edge, explained in full. We’ll go over what each number means, how they relate to each other, where to find them, and how to use them when choosing which online casino games to play.

Whether you're comparing slot titles, deciding between European and American roulette, or trying to figure out why video poker gets recommended so often, we'll help make those decisions clearer.

What is RTP in an online casino?

RTP stands for Return to Player, and it represents a theoretical percentage of wagered money that will be paid back to players over time.

A simple example: a slot with a 96% RTP is mathematically designed to return $96 for every $100 wagered across millions of rounds. The remaining $4 is the casino's margin.

The key word here is "theoretical." RTP doesn't guarantee what will happen in your session today, this week, or even this month. It describes what happens across an enormous sample size, sometimes trillions of rounds, and the actual experience of any individual player in any individual session can look radically different.

You can win significantly more than 96% of your stake in a session, but you could also lose your entire stake without any meaningful wins.

What does house edge mean?

The house edge is the casino's built-in mathematical edge on a game, expressed as the percentage of every wager the casino expects to keep as profit over the long run. It is the mirror image of RTP.

Where RTP tells you what comes back to players, house edge tells you what stays with the house. A 4% house edge means the casino expects to retain $4 from every $100 wagered over time.

This margin is built into the game's mathematics by its designers before it ever reaches a casino floor or a website, so it is not something the casino controls game by game, and it doesn't change based on who is playing or how a recent session went.

The house edge is why casinos are profitable businesses regardless of individual player results. Not because they win every bet (they don't), but because the mathematical structure of every game they offer ensures a predictable profit margin, given enough wagering volume.

How RTP and house edge relate to each other

RTP and house edge are two expressions of the same underlying facts, and they always add up to 100%. The RTP represents the money that will be paid out to players, the house edge represents the money that will go to the casino.

The formula is straightforward:

House Edge = 100 − RTP

So a game with 96% RTP has a 4% house edge, a game with 98% RTP has a 2% house edge, and so on.

How RTP is calculated

Game developers arrive at RTP figures through mathematical modeling and simulation rather than by tracking real-world play. Before a game is released, the studio's mathematicians build a model of every possible game state, every reel combination, every bonus trigger probability, and every payout, then simulate millions or billions of theoretical rounds to calculate the theoretical long-term results.

This is why RTP is considered a theoretical figure. It reflects the expected return over a huge number of plays, far more than any individual player will experience.

For example, you might play 1000 spins on a 96% RTP in one session, which is a very small sample compared to the millions of spins used to calculate RTP. Over those 1000 spins, you could win much more or much less than the 96% theoretical return.

Independent testing laboratories, including eCOGRA, GLI (Gaming Laboratories International), and iTech Labs, verify that game studios' published RTP figures accurately reflect the underlying mathematics before games are certified for use at licensed casinos.

Where to find a game's RTP

For slots, the simplest way to find the RTP is the in-game information or paytable screen. Most modern slots include a small info button (often labeled "i" or "?") that opens a detail panel listing the RTP, volatility rating, and payline structure. This should be the first place to look.

If the in-game panel doesn't display the RTP, most major studios (NetEnt, Pragmatic Play, Play'n GO, Evolution) publish RTP figures for their full game catalogs in the game details pages on their websites. Reputable casino game review sites also list RTPs as a standard part of their game profiles.

Some operators configure their games at the lower end of a provider's permitted RTP range without disclosing this clearly. Most providers allow operators to choose from a range of RTP settings; a game might be offered in 94%, 96%, or 96.5% RTP variants, depending on what the operator selected at the time of integration.

Average RTP and house edge by game type

With RTP and house edge explained, it’s also important to understand what you can expect from different types of games.

Slots RTP and house edge

Slot RTPs range widely, commonly from around 90% at the low end up to 98-99% for high-RTP titles, though 95-97% is the most common range at reputable licensed operators.

The variance between titles is significant enough that game selection matters for long-run expected value. Mega Joker from NetEnt publishes a 99% RTP; some lower-quality slots from less regulated markets sit below 90%.

Checking the RTP before selecting a slot is the single easiest change you can make to improve your theoretical odds. Explore the full range of options at online casinos to compare platforms that publish RTP clearly.

Blackjack house edge

Blackjack has one of the lowest house edges of any casino game, often around 0.5% when played with basic strategy. That means the casino expects to keep just $0.50 of every $100 wagered over time, if a player makes mathematically optimal decisions on every hand.

Without basic strategy, the house edge rises, often to 2-3% but can easily go into double digits for players making poor decisions.

Roulette house edge

The single most important decision in roulette, from a house edge perspective, is which wheel to play on. European roulette's single-zero wheel carries a house edge of 2.7%. American roulette's double-zero wheel carries a house edge of 5.26% – nearly double.

On even-money bets specifically, European roulette's La Partage rule (half the stake returned when the ball lands on zero) halves the effective house edge to 1.35%.

When both options are available, choosing European over American roulette is the simplest house-edge improvement you can make at a roulette table, with no strategy required.

Video poker and other table games

Video poker is the table game category where player decisions have the most impact on the effective house edge. With optimal strategy applied, some video poker variants (Jacks or Better, Deuces Wild) can offer a house edge below 1%, and the best-paying Deuces Wild paytables at properly maintained machines can theoretically exceed 100% RTP (meaning slightly player-positive) with perfect play.

Baccarat's banker bet carries a house edge of approximately 1.06%, one of the lowest of any fixed table game and requiring no skill to access, since the betting decision is the entire strategic component. If you're focused purely on house edge with minimal complexity, baccarat's banker bet is one of the most efficient options you can choose.

Does RTP affect how often you win?

Many players believe that RTP directly affects the outcome of their gameplay, and it’s one of the most persistent misunderstandings around RTP.

A game's RTP tells you about the proportion of all money wagered that comes back to players over the long run. It has virtually no meaningful bearing on any individual game session.

That's where volatility (also called variance) comes in. Volatility is a separate characteristic from RTP and describes the distribution of outcomes, how frequently a game pays, and how much it pays.

A high-volatility slot might have a 96% RTP and pay out infrequently, with winnings concentrated in occasional large hits. A low-volatility slot with the same 96% RTP might pay more often but in smaller amounts. Both games return the same theoretical percentage over millions of spins, but the experience can feel completely different.

How to use RTP and house edge to choose games

RTP and house edge are useful inputs into game selection, but they work best as one factor among several rather than the only deciding factor. Practical guidance:

• Favor higher RTP when comparing similar games. Between two slots with comparable themes and mechanics, the one with a higher RTP represents better long-term value.
• Understand that a lower house edge improves long-term odds but never eliminates the casino's advantage. Even a 0.5% house edge in blackjack means the casino has an edge. The goal of using RTP and house edge data is to minimize the mathematical disadvantage, not to eliminate it.
• Factor in volatility alongside RTP. A high-RTP, high-volatility slot may burn through a small bankroll quickly. If you have a limited budget, a slightly lower RTP with lower volatility will let you get more play time out of your bankroll.

For a full guide library covering bankroll management, game strategy, and platform comparisons, our online casinos guides section covers each topic in detail.

Common myths about RTP and house edge

To wrap up, let’s debunk some common myths surrounding RTP and house edge:

• "This machine is due for a win." Every spin of a slot, every hand of blackjack, and every roulette spin is independent. A long losing streak does not increase the probability of a win in the next round.
• "RTP resets or changes based on recent results." RTP is a fixed mathematical property of the game. It does not change based on how a specific machine has performed recently, how much money has been paid out in a session, or what time of day it is. The only way a game's RTP changes is if the operator reconfigures it within the provider's permitted range, which doesn’t happen in response to individual sessions.
• "A high RTP means I'll win more in my session." A 98% RTP slot can produce a complete loss in a short session just as a 94% RTP slot can produce a large win. RTP describes the long-term performance across millions of spins, not the outcome of a regular session.
• "Casinos adjust RTP based on player behavior." Licensed casinos in regulated jurisdictions cannot dynamically alter the RTP of a game mid-session or in response to individual player behavior. The configured RTP is a fixed setting applied during integration, and changing it is a complex process that doesn’t happen on the fly.

RTP and house edge FAQs