How Slot Bonus Rounds Work: Free Spins, Multipliers & More

Bonus rounds are where the biggest wins in slots happen. This guide explains every type of bonus feature, from free spins to cascading reels, and how to use them strategically.

What Are Bonus Rounds?

Bonus rounds are special game modes triggered within a slot that offer enhanced win potential above and beyond the base game. They are the primary source of high wins in most modern slots and the feature that most players are actively trying to trigger.

Free Spins (Free Games)

The most common bonus type, found across our most popular slots and new releases. Typically triggered by landing 3 or more Scatter symbols anywhere on the reels. During free spins:

  • Your bet is not deducted per spin
  • Multipliers may be active throughout
  • Retriggers are often possible
  • The RTP of the game is sometimes higher in free spins mode

Pick Bonus / Pick and Click

A selection based bonus where you choose from hidden items to reveal prizes. These often have a predetermined outcome but provide an interactive element. Common in older slots and casual games.

Cascading / Avalanche Reels

After a win, winning symbols explode or fall away and new symbols drop in to replace them. This can create consecutive wins from a single spin. Combined with an increasing multiplier on each cascade (as in Sweet Bonanza), this mechanic creates enormous win potential.

Hold & Win / Respins

Triggered by landing a specific number of special symbols (usually gold coins or orbs). The triggering symbols lock in place while the remaining reels respin, aiming to add more locked symbols. A full board of locked symbols typically awards the Grand Jackpot.

Bonus Buy Feature

Some games allow you to purchase direct access to the bonus round for a set cost, typically 50–100× your current bet. Note: Bonus Buy is prohibited in the UK and some other jurisdictions.

Megaways Bonus Rounds

Megaways slots often feature free spins with an increasing multiplier that builds with each consecutive win, pioneered by Big Time Gaming in games like Bonanza, it can produce multipliers of 50× or more.

How to Maximise Bonus Round Value

  • Always play at the maximum bet if using a buy bonus feature
  • For triggered bonuses, bet size at trigger determines the prize
  • High volatility bonus rounds are rarer but pay more : match to your bankroll