Trigger meaning in slots

Trigger meaning in slots: the definition

To trigger a feature is to meet the condition that starts it. On most video slots that means landing a set number of scatter symbols or bonus symbols anywhere on the reels during one spin. When it happens, the game usually pauses, plays a short sequence and moves into the bonus game or feature.

The same word also describes what qualifies you for a casino promotion, such as betting £10 to receive offer spins, which is a different thing entirely. This entry is about in-game triggers; the rest of the vocabulary is in our slot glossary.

Types of trigger on slot machines

Book of Dead is the classic book-style scatter trigger, using the book symbol as both wild and scatter. Sweet Bonanza uses scatters anywhere on a 6 × 5 grid. Collection designs are explained under cash collect, and random ones under random features.

Trigger odds: a worked example

Here is a simplified game where the bonus symbol appears only on reels 1, 3 and 5, and each of those reels has a 1 in 10 chance of showing it in the window on any spin.

1. Chance of all three on one spin: 1/10 × 1/10 × 1/10 = 1 in 1,000.
2. Average spins between triggers: 1,000.
3. At 20p a spin, that is £200 staked on average between features.
4. Chance of no trigger at all in 1,000 spins: about 37% (0.999 multiplied by itself 1,000 times).
5. Chance of no trigger in 2,000 spins: about 14%, so long droughts are normal.

Those numbers are invented to show the method, not taken from a real game. Real trigger rates are set in the developer's maths model and rarely published. The page on bonus trigger odds shows how to reason about them, and how many spins until a bonus explains why only averages exist.

Why a trigger is never ‘due’

On random games every spin is independent, so 500 spins without a feature do not make the next spin more likely to trigger one. Believing otherwise is the gambler's fallacy. The exception is a visible collection meter: there, progress is real and shown on screen, and the rules say what fills it.

Two scatters with the third just out of view is a near miss, not a sign of an approaching trigger. Games often slow the last reel in that situation, an effect called the anticipation spin, but the result was settled before the reels started moving. Our list of slot machine myths covers several more.

Triggers on fruit machines

On British fruit machines, features usually start from symbols on the main reels or from number reels that move you along a trail. Many of these machines are compensated, so how often features are offered can depend on recent payouts, and the machine must state whether it is random or compensated. Pub Category C machines allow up to £1 per game and a £100 top prize, and are for players aged 18 and over.

UK rules relevant to triggers

Players in Great Britain cannot pay to skip the trigger, because UK-licensed slots do not offer bonus buys. Online slots must take at least 2.5 seconds per spin and must not celebrate a return equal to or smaller than the stake, so a trigger that pays back less than you have staked is not dressed up as a win. Game rules, including trigger conditions, are covered by the remote gambling and software technical standards (opens in a new tab).

Chasing a trigger by raising stakes or extending a session is a common route to losing more than planned. If that pattern sounds familiar, GamCare (opens in a new tab) runs the free National Gambling Helpline on 0808 8020 133, 24 hours a day.

Offer triggers at Coral and Ladbrokes

The partner offers have their own qualifying triggers, separate from anything in a game. At Coral, a new player aged 18+ triggers 100 free spins by depositing and betting £10 or more on slots; the spins are 10p each on selected games, must be accepted within 48 hours, last 7 days and have no wagering on winnings. At Ladbrokes, a new customer aged 18+ who deposits and spends £10 on slots receives 50 free spins a day for 10 days, up to 500 at 10p each, to claim before 23:59 each day, with no wagering. Some deposit methods do not count and terms apply. Both are run by LC International Limited. Our page on bet £10 get free spins offers explains the structure.

18+. Gambling should be entertainment that costs money, not a way to make it. Decide a budget before you play: plan a slot budget. Free, confidential help: National Gambling Helpline 0808 8020 133.