Bonus features
Where most of a modern machine's excitement, and much of its return, sits.
By Ryan Jessop. Last checked .
Key takeaways
- Free spins: the commonest feature.
- Wilds: expanding, sticky, walking.
- Multipliers and cascades.
- No buying features in Britain.
In shortBonus features are special rounds or modifiers triggered at random, usually by scatter symbols. Free spins are the commonest.
Features
| Feature | What happens | Example |
|---|---|---|
| Free spins | A set of spins at no cost, often with extras | Book of Dead |
| Expanding wild | A wild grows to fill its reel | Starburst |
| Cascades or tumbles | Winning symbols vanish and more fall | Sweet Bonanza |
| Multipliers | Wins are multiplied | Gates of Olympus |
| Cash collect | A collector gathers cash values | Big Bass Bonanza, Fishin' Frenzy |
| Pick bonus | Choose items for prizes | Fluffy Favourites |
Each feature in full
- Hold buttons
- Nudges
- feature trail
- hi-lo gamble
- Free spins features
- Wild symbols
- Scatter symbols
- Multipliers
- Cascading reels
- Hold and win
- Cash collect
Triggering
Usually three or more scatters. It can take hundreds of spins on a volatile machine.
In Britain
Features cannot be bought. They arrive through ordinary play.
Keep reading: UK slot machine categories, Book of Dead slot machine, Slot machine myths and Compare slot machines.
Where the return sits
On a low-volatility machine most of the return comes from ordinary line wins. On a high-volatility one a large share is locked in the feature, which is why long stretches of base-game play can feel so unrewarding.
Retriggers
Many free spins rounds can be extended by landing more scatters during them. On Big Bass Bonanza every fourth fisherman adds ten spins and raises the multiplier.
Gamble features
Some machines offer to double a win on the turn of a card. It is a fair 50-50 with no house edge, and it raises volatility sharply.
Go further: Should you bet max on a slot machine?, Pub slot machines and Gem and diamond symbols.
In other words
Bonus features, bonus rounds, bonus games and slot features are four names for one thing: anything a slot does beyond its ordinary spins.
Keep reading: Casumo slot machines, The BAR symbol, Ways-to-win slot machines and Return to player.
Slot figures are developers' published defaults, each confirmed against two sources; the version at your casino can differ. UK land-based stake and prize limits and online rule dates were checked against Gambling Commission and licensing authority sources on 6 October 2026. History follows commonly cited accounts. Offer terms dated 5 October 2026. How we check. 18+. Free help: 0808 8020 133 or safer gambling.
Frequently asked questions
What are slot bonus features?
Special rounds or modifiers.
How do I trigger free spins?
Usually three scatters.
Can I buy a feature?
Not in Britain.
What is a cascade?
Winning symbols replaced by new ones.