Online slots come packed with bonus features, and understanding how they work can make your playing experience a lot more enjoyable. While every spin is ultimately determined by luck — thanks to Random Number Generators (RNGs) — knowing what the different features do helps you appreciate what’s happening on screen and get the most entertainment out of your sessions.
Here’s a rundown of the most common slot bonus features you’re likely to come across when playing at a UKGC-licensed casino site.
Wild Symbols
The wild symbol is often described as the joker of the slot world. Its main job is to substitute for other symbols on the reels, helping you complete winning combinations that you might otherwise have missed.
Wilds typically cannot replace scatter or bonus symbols, but beyond that restriction, they’re extremely useful. Landing a wild in the right position can be the difference between a near-miss and a payout.
There are actually several different types of wild symbols, and different games use them in different ways:
Expanding Wilds — When an expanding wild lands on a reel, it stretches to cover the entire reel. This means it can help create wins across multiple paylines at once.
Sticky Wilds — These wilds stay in place for a set number of spins, usually during a free spins round. While the other reels keep spinning, sticky wilds remain locked, giving you extra chances to land wins.
Random Wilds — These appear in random positions on the reels, adding an element of surprise to any spin. Some games place several random wilds at once.
Walking Wilds — A walking wild moves one position across the reels with each spin, usually from right to left, until it drops off the edge. Each move gives you another chance at a winning combination.
Multiplier Wilds — These don’t just substitute for other symbols; they also multiply any win they’re part of. A wild with a 2x or 3x multiplier can significantly boost your payout on a winning line.
Scatter Symbols
Scatter symbols work differently from most other symbols because they don’t need to land on a specific payline to be useful. They can appear anywhere on the reels and still trigger payouts or bonus features.
The traditional scatter simply pays out based on how many appear on the reels, regardless of position. Two scatters might give a small payout, three a bigger one, and so on.
Multiplier scatters take things further. Landing multiple scatter symbols can multiply your total win for that spin. For example, two scatters might double your win, three could quadruple it, and four might multiply it by nine times.
Most importantly, scatters are usually the key to unlocking bonus rounds. Landing three or more scatters typically triggers the game’s main bonus feature, whether that’s free spins, a pick-and-click game, or something else entirely.
Free Spins
Free spins are probably the most popular bonus feature in online slots. When triggered — usually by landing three or more scatter symbols — you’re awarded a set number of spins that don’t cost you anything. Any wins during these spins are added to your balance.
Free spins rounds often come with extras like multipliers, additional wilds, or expanding symbols that make wins easier to land. Some games even let you retrigger free spins during the bonus round by landing more scatter symbols.
Pick-and-Click Bonus Games
Some slots feature interactive bonus rounds where you pick from a selection of hidden items to reveal prizes. These mini-games break up the standard spinning action and can award instant cash prizes, multipliers, or additional free spins. They add variety to the gameplay and give you the feeling of having some input, even though the prizes are still determined by the RNG.
Gamble Features
A number of slots include a gamble feature that appears after a win. This usually involves guessing the colour or suit of a hidden playing card. Guess correctly and your win is doubled (or quadrupled if you guess the suit). Guess wrong and you lose the win entirely. It’s a high-risk, high-reward option that adds a bit of extra excitement.
Cascading Reels
Also known as tumbling reels or avalanche features, cascading reels remove winning symbols from the board after a win and replace them with new symbols dropping from above. This can lead to chain reactions of multiple wins from a single spin, and some games increase a multiplier with each consecutive cascade.
Staying Safe While Playing
Whatever slot features you enjoy, always make sure you’re playing at a site licensed by the UK Gambling Commission. This ensures the games are fair and your money is protected. It’s also worth remembering that credit cards cannot be used for gambling in the UK, so you’ll need to use a debit card, e-wallet, or another approved payment method.
Set yourself a budget before you start playing and stick to it. If you ever feel that gambling is becoming a problem, GambleAware offers free advice and support. For more on how slots work, check out our other guides.