Online slots in Canada: how they work

How a slot decides each spin

Every slot runs on a random number generator, or RNG: software that produces numbers continuously, thousands of times a second. When you press spin, the game takes the current number and maps it to a stop position on each reel. The spinning animation that follows only displays a result that is already fixed. Stopping the reels early, changing the speed or waiting between spins does not change what you get.

The game provider builds the RNG and the paytable, and an independent test lab checks both before a regulator allows the game to go live. Labs such as GLI, BMM, iTech Labs and eCOGRA run millions of simulated rounds to confirm that the results are random and that the long-run return matches what the provider states.

A slot has no memory. A game that has not paid for a while is not "due", and one that has just paid a large win is not "cold". Every spin is independent of the last one. Believing otherwise is called the gambler's fallacy, and it is an expensive idea to bring to a slot.

RTP: the payout percentage

RTP, short for return to player, is the share of all the money staked on a game that it pays back as winnings over its whole life: millions of spins across every player, not your evening. A slot with an RTP of 96% keeps on average 4 cents of every dollar wagered on it. That 4% is the house edge.

The gap between "on average" and "tonight" is the whole point. As a worked example only, on a 96% slot at $1 a spin:

• 100 spins. You stake $100 and the label predicts a loss of $4. In practice one decent bonus round can put you $50 ahead, and a run with no feature at all can cost $60 or more. The $4 is buried under swings ten times its size.
• 100,000 spins. You stake $100,000 and the label predicts a loss of $4,000. The swings are now a few percent of everything staked, and the result starts to look like the label.

RTP is real, but it only shows up over more play than anyone reaches in one sitting. It is also not a fixed property of a game. Providers commonly release one title in several RTP versions, for example 96%, 94% and 92%, and the casino chooses which one to install. Same game, same graphics, different price: on $100 staked, the 96% version costs $4 on average and the 92% version $8. We cannot verify which version a given casino runs, and a casino can change it, so we do not publish casino-specific RTP figures. The version running in front of you is the one its info panel shows. Hacksaw Gaming's Plinko is an extreme case, with seven versions from 88.20% to 98.98%.

Volatility: how often against how much

Volatility, also called variance, describes how a slot pays out its RTP: many small wins, or rare large ones. Providers give it as a label (low, medium, high, or a scale such as 1 to 5) rather than a figure, and no regulator sets it.

Two slots with the same 96% can feel nothing alike. A low-volatility game such as Starburst lands small wins often, and the balance drifts rather than drops. A high-volatility game such as Book of Dead can go a long stretch with little, and the session hangs on its free spins round: many sessions end before it arrives, and the few that catch a good one can end far ahead. Neither is the better game. Low volatility buys time; high volatility buys a chance at a large hit, at the cost of more short sessions. Pick the level that suits your budget and your patience.

Some info panels also show a hit frequency, the share of spins that return anything at all, and a maximum win, such as 5,000x the stake. A "hit" includes wins smaller than the stake, so a 30% hit frequency does not mean you are ahead on 30% of spins.

Paylines, ways to win and Megaways

Paylines. Classic slots and many video slots pay when matching symbols land on fixed lines across the reels, usually starting from the leftmost reel. Ten, 20 and 25 lines are common. Where you can switch lines off, fewer lines make each spin cheaper and win less often; in most such games the return per dollar stays the same.

Ways to win. Games with 243 or 1,024 ways pay for matching symbols on adjacent reels from the left, in any row. On five reels, 243 ways means three rows (3 x 3 x 3 x 3 x 3) and 1,024 ways means four rows.

Megaways. Megaways is a reel mechanic licensed by the provider Big Time Gaming. On every spin each reel shows a random number of symbols, typically 2 to 7 on six reels, so the number of ways to win changes from spin to spin, up to 117,649 (7 x 7 x 7 x 7 x 7 x 7). Most Megaways games add cascades, also called tumbles: winning symbols disappear, new ones drop into their place, and one spin can produce a chain of wins. Many also have a win multiplier that grows during free spins. More ways does not mean better value: the paytable is set so the game returns the RTP the provider states, and Megaways games often sit at the higher end of volatility. Check the label in the info panel.

Cluster pays. Some grid games pay for groups of touching symbols, for example five or more of a kind, instead of lines.

Bonus features

• Free spins. The most common feature, usually started by three or more scatter symbols anywhere on the reels. Free spins often switch on extras the base game lacks: win multipliers, sticky wilds that stay in place for the round, or a symbol that expands to fill a whole reel.
• Hold and win (respins). Only money or jackpot symbols stay on screen. You start with a few respins, usually three; each new money symbol sticks and resets the counter. The round ends when the respins run out or the screen fills, which often pays a fixed top jackpot.
• Pick and click. A second screen of objects to choose from, each hiding a cash prize, a multiplier or extra spins, until you reveal a "collect" symbol.
• Wheel bonus. A wheel of prize segments, sometimes leading to a higher-tier bonus or a progressive jackpot.
• Gamble feature. After a win, an option to guess a card's colour to double it, or its suit to quadruple it. A wrong guess loses that win. It adds risk without improving the long-run return.
• Bonus buy. Some slots let you pay a set price, often around 100x the stake, to start the feature at once. The bought feature has its own RTP, shown in the info panel, and a bonus buy uses up a budget very quickly. Bonus terms often forbid it while a bonus is active.

Jackpots: fixed and progressive

A fixed jackpot is a top prize set as a multiple of the stake, for example 5,000x, and it is part of the game's normal RTP.

A progressive jackpot grows with a small share of every bet until someone wins it. A local progressive grows inside one game at one casino; a network progressive pools bets from many casinos, which is how prizes reach seven figures. Mega Moolah is a long-running example. Three things follow. The share of each bet that feeds the jackpot is part of the RTP, so the base game usually returns less than a comparable slot without one. The chance of the top prize on any spin is very small. And some games make only certain bets eligible for the top prize, which the jackpot rules in the info panel state. Some casinos also run "must drop" jackpots that have to pay out before a set time or amount; the rules say which.

How to read a slot's info panel

Every slot has a rules or help screen, usually behind an "i", a "?" or the menu icon. Open it before you play with real money and look for:

1. RTP. The figure for the version installed at that casino, and sometimes a second figure for the bonus buy.
2. Volatility. The provider's label or scale.
3. Maximum win. The cap on a single spin or feature, written as a multiple of the stake.
4. Minimum and maximum bet. What one spin costs at either end.
5. Paytable. What each symbol pays at your stake, and which symbols are wild or scatter.
6. Feature rules. How free spins and other features start, retrigger and end.
7. Jackpot rules. Eligibility and how the jackpot is paid, if the game has one.
8. Malfunction clause. The standard line that a malfunction voids all pays and plays.

If the same game is offered at two casinos and the number matters to you, compare the RTP in both panels: it can differ.

Slots and bonus wagering

Slots usually count 100% toward a wagering requirement, which is why most casino bonuses are built around them. The terms still limit how you play while a bonus is active: some slots are excluded by name, often high-RTP or jackpot games; bonus buys are often not allowed; and a maximum bet applies to every spin. Breaking one of these rules can cost the bonus and the winnings tied to it.

As a worked example only: a $100 bonus at 35x needs $3,500 in bets. At a 96% slot, $3,500 in bets costs about $140 on average, so the expected result is about $40 below the $100 bonus, before any cap on winnings. Volatility matters as much as RTP here: a low-volatility slot keeps the balance alive long enough to get through the requirement, and a high-volatility slot is more likely to empty it first. The full arithmetic is in our guide to wagering requirements.

Demo play

Many casinos and providers let you play a slot in demo mode with play credits. It is a sensible way to learn how a game's features start, how often it pays at its volatility, and where its info panel sits, before any money is involved. Two limits apply. Demo credits are not money and demo wins cannot be withdrawn. And a short demo session says nothing reliable about what real play will return, for the same reason a short real session does not: the swings are bigger than the edge. Some casinos only show demos after you open an account and confirm your age.

Set your limits before you spin

Slots are fast. At a spin every three or four seconds, an hour is roughly 900 to 1,200 spins. As a worked example only: at $1 a spin on a 96% slot, an hour of play is about $1,000 staked and costs about $40 on average, with swings far bigger than that. Quick-spin and turbo settings add spins per hour, and so add cost per hour at the same RTP. Autoplay makes it easy to stop counting.

Use the tools in your casino account before your first deposit: a deposit limit, a loss limit, a session reminder or time limit, and, if you need it, a time-out or self-exclusion. Decide your budget for the session, stop when it is gone, and never raise your stake to win back a loss.

Where to play

Our Canadian list shows the casinos we cover. For a casino's licence, payment methods, account currency and terms in one place, start from our casino reviews. The terms used on this page are defined in the casino glossary.

More guides in the academy

• Online roulette: wheels, bets and house edge
• Online blackjack: rules and house edge
• Online baccarat: Banker, Player and Tie
• Live dealer casinos: how live games work
• Wagering requirements explained, in dollars
• Casino glossary
• Beginner's guide to online casinos in Canada

A slot is entertainment with a price, not a way to make money. If gambling stops being fun, our responsible gambling page lists free, confidential help for every province we cover.