Booster has been catching plenty of attention, so we put it through its paces to see how it really holds up. Built by iSoftBet, it lands as a title with medium high volatility and an RTP of 95.99%. It first went live in 2020 and still earns its place today. The maximum win sits at 12,000x, so there's serious upside on the table. It's wrapped in polished, characterful visuals and plays out on a 5-reel grid running 40 paylines. Here's how it stacks up.
Written by Alex Crawford · Last updated: February 2026
Booster comes to us from iSoftBet. Presentation-wise it's built with crisp artwork and atmosphere, and it leans toward a medium high-variance maths model at a published RTP of 95.99%. Under the hood you'll find a 5-reel grid running 40 paylines.
Where Booster earns its keep is the feature set. Look out for scatter symbols that unlock free spins and extra bonus rounds. Its medium high variance balances steady wins with the odd larger payout. All told, it's a solid entry in the iSoftBet catalogue.
At 95.99%, the RTP is slightly below the industry average of ~96%. While this is typical for many popular slots, players should be aware of the slightly lower theoretical return.
Medium-high volatility means wins come less frequently but tend to be larger when they hit. Players should be prepared for dry spells between bigger wins, requiring a moderate bankroll.
About 1 in 3 spins results in a win. This is a moderate hit frequency that balances win frequency with payout size.
Booster features scatter symbols that can trigger free spins rounds. Landing the required number of scatter symbols anywhere on the reels activates the free spins feature, giving you extra chances to win without additional bets. During free spins, special modifiers may apply to boost your winning potential.
3.0 / 5 — Good
Booster by iSoftBet is a solid offering that delivers good entertainment value. The 95.99% RTP combined with medium high volatility creates a well-balanced gaming experience.