Bonus round in slots
A bonus round is a separate feature inside a slot game, triggered by a specific event on the reels, that plays out under different rules from the base game. The usual trigger is a set number of scatter symbols, often three or more, though the exact condition is set by each studio in the game’s paytable. Free spins, pick-and-win screens and wheel features are all common forms. The round runs on the same RNG as the rest of the game, so the outcome is already random rather than earned.
Where the bonus round sits in the maths
A slot’s published RTP covers the whole game, base spins and bonus rounds together, and studios often attribute a large share of that return to the feature. That is why a game can feel stingy for long stretches and then pay heavily in one round.
The trigger frequency, how often the round arrives on average, is a long-run figure and varies widely between titles; where a studio publishes it, the paytable or game information screen is where it appears.
No slot is ever due a bonus. Each spin is independent, so two hundred dry spins change nothing about the next one.
What a bonus round is often confused with
The phrase is easily mixed up with a casino bonus, which is a promotional offer from the operator, usually carrying wagering requirements. A bonus round belongs to the game itself and costs nothing extra to trigger in normal play.
Free spins cause the most confusion, because the same words describe two different things: a feature inside the slot, and a promotional allocation of spins credited by the casino with its own terms attached. What we check first is which of the two a page means.
Some games also offer a bonus buy, where the player pays a multiple of the stake to enter the round directly; availability and pricing differ between studios and markets.
