Bonanza occupies a unique position in slot history as the original Megaways title. When Big Time Gaming released it in 2016, the variable-reel mechanic was new, the 117,649-ways branding was unfamiliar, and the gold-mining theme felt almost incidental compared to the novelty of the underlying maths. The published theoretical RTP of 96.00% sat in line with mainstream expectations of the era, and the slot quickly became a touchstone for what high-volatility Megaways gameplay could feel like. Two years later, Extra Chilli arrived with a Mexican-market street-food theme and a refined version of the same engine, plus two notable additions: a feature-buy option and a gamble mechanic that allowed players to risk earned free spins for the chance at more spins with higher multiplier ceilings.
RTP comparison
On paper, Extra Chilli's 96.15% theoretical edges ahead of Bonanza's 96.00% by 0.15 percentage points. Over £10,000 of wagering volume, that is a £15 difference in expected return — small enough that it should not drive game selection on its own. Both titles sit on Big Time Gaming's fixed-RTP deployment model. BTG operates differently from variable-tier providers like Pragmatic Play or Play'n GO; the studio publishes a single RTP per title and deploys that figure consistently across its UK distribution network. This means the published comparison is the deployed comparison. There is no tier matrix sitting between the published number and the actual configured value at your casino. For a fuller explanation of why this matters, see what is RTP.
Volatility profiles
Both slots are categorised as high volatility, but Extra Chilli sits at the upper end of that band thanks to the gamble mechanic on free spins. After triggering a free spins round, players can choose to gamble their earned spins on a coin-flip basis — guess correctly and the spin count increases (with progressively higher multiplier ceilings), guess wrong and the spins are lost entirely. This mechanic adds a layer of variance that pure-maths volatility ratings do not fully capture. Players who use the gamble feature aggressively will experience longer dry runs and more extreme sessions than the headline volatility rating suggests. Bonanza has no equivalent mechanic — its variance comes purely from the standard Megaways structure plus an unlimited-multiplier free spins round. For a deeper dive into how variance works in practice, our volatility explained guide covers the underlying mechanics.
The feature buy
Extra Chilli's feature buy lets players purchase direct entry to the free spins round at a fixed multiplier of stake. The published RTP for the bought feature is technically the same 96.15% — the maths is calibrated so that the expected return on a single feature purchase matches the expected return on the equivalent organic play. In practice, the feature buy concentrates volatility further: you skip the base-game grind and go directly to the high-variance bonus round, where outcomes can vary wildly from the published average over small samples. This is a player-preference question rather than a mathematical advantage. UK regulatory changes have restricted feature-buy availability on some Pragmatic and Play'n GO titles, but Extra Chilli's gamble-style structure has historically remained available in the UK market.
Deployed RTP across UK casinos
BTG's consistent-deployment model means the comparison is straightforward. At Bet365, Bonanza runs at 96.00% and Extra Chilli at 96.15%. At LeoVegas, Ladbrokes, and other major UK operators, the same figures hold. There is no operator-by-operator variance to track because BTG does not offer one. This is unusual in the modern UK market — most providers offer at least three tiers and many casinos select below the maximum on portions of their catalogue. BTG's approach is closer to the older fixed-RTP model that NetEnt used pre-2020.
Verdict
The maths gap is small enough that it should not be the deciding factor. Both slots offer high-quality Megaways gameplay at deployed RTPs that sit comfortably above the UK industry average. Extra Chilli wins narrowly on theoretical RTP, on feature variety thanks to the gamble mechanic and feature buy, and on overall pace. Bonanza wins on historical significance and on slightly cleaner gameplay for players who find Extra Chilli's additional features distracting. For new players approaching either title for the first time, Extra Chilli is the better introduction. For Megaways purists who want the original experience, Bonanza remains the reference point.