Online slots in Canada: how slots really work

How an online slot decides a result

Every online slot runs on a random number generator (RNG): software that produces a constant stream of random numbers. When you press spin, the game takes the current number and maps it to a position on each reel. The spinning animation is just a display of a result that was fixed the moment you pressed the button.

Two things follow from that. First, each spin is independent: what happened on the last spin, or the last hundred, has no effect on the next. A slot is never "due" a win, and a machine that has just paid is not "cold". Second, nothing you do during the spin, such as stopping the reels early, changes the outcome.

The game's maths decides how likely each outcome is and how much it pays. That maths includes a built-in margin in the casino's favour, which is how the casino makes money over time. It is sometimes called the casino's edge.

Volatility explained

Volatility (sometimes called variance) describes the shape of a slot's payouts, not their total.

Low volatility games pay small wins often. Your balance tends to move slowly, and sessions last longer on the same budget.

Medium volatility games mix regular small wins with occasional bigger ones.

High volatility games pay less often, with long runs of losing spins, but can pay larger amounts when they do. A session can end quickly.

Volatility changes how a game feels, and how fast a budget can go, but not the built-in margin. Some game makers describe volatility in the game's information panel; if yours does not, a demo mode is the easiest way to get a feel for it.

What RTP means

RTP stands for "return to player". It is the share of all money staked on a game that the game is designed to pay back, averaged over an enormous number of spins. It is published by the game maker, varies by game, and can sometimes vary between versions of the same game.

RTP is a long-run average. It tells you nothing reliable about a single session: in the short term, anything can happen. The gap between the RTP and a full return is the built-in margin. We do not print RTP figures on BetNook, because we have not verified them for the versions offered in Canada. You can usually find a game's published figure in its information panel.

Slot features

Wilds substitute for other symbols to help complete winning lines. Scatters pay wherever they land and often trigger bonus rounds. Free-spin rounds are in-game features that award spins as part of the game's own maths; they are different from bonus free spins given by a casino, which our free spins guide explains. Multipliers increase wins by a factor. Jackpots come in two main kinds: fixed jackpots with a set top prize, and progressive jackpots that grow as players stake on a linked game. Progressive jackpots are hard to win, and a large jackpot on the screen does not make any spin more likely to hit it.

Common slot myths

"This machine is due." No slot is ever due. Each spin is independent, so a long losing run does not make a win more likely.

"Playing at night pays better." The time of day has no effect on results. The random number generator does not know what time it is.

"Casinos switch payouts when you win." A game's maths is fixed when it is built and certified. The casino does not turn it up or down while you play.

"Bigger bets change the odds." On most slots, the chance of each outcome is the same whatever you stake. Bigger bets change the size of wins and losses, not how often they happen.

Choosing a slot

There is no "best" slot in terms of your chances; the maths is fixed. What you can choose is a game that suits how you want to play. If you want long, steady sessions, look for lower volatility. If you prefer the chance of a bigger win and accept that sessions may be short, higher volatility fits. Read the information panel for features and the published return figure, and try a demo if one is offered. Themes and graphics are a matter of taste; they do not change the odds.

Where to play: our ranked list of online casinos covers the sites we have checked, and every one opens in a phone browser (see mobile casinos).

Safer slot play

Slots are fast. A single spin takes seconds, so money can move quickly without it feeling like much. Decide your budget before you start and stop when it is gone. Set a session time limit, and use the reality-check or time-out tools if the site offers them.

Never chase losses: the next spin is independent of the last, so playing on to "win it back" only increases what you stand to lose. Treat any win as luck, not a sign. If slots stop being fun, take a break, and see our responsible gambling guide for tools and free support.

More reading: all guides for Canadian players.