The mechanic behind Megaways — why the number of ways to win changes on every single spin, how the RNG actually decides each reel's height, how the maths behind 117,649 adds up, what "Reel Kingdom" has (and hasn't) got to do with it, and why the same Megaways title can carry a noticeably different RTP depending on which studio licensed it

Megaways is the single most widely licensed slot mechanic of the last decade, appearing in games from a dozen different studios under one shared underlying system. It looks dramatic on screen — reels of different heights, cascading wins, a "ways to win" counter that changes every spin — but the actual mechanic behind it is a specific, patented piece of mathematics, not just a visual flourish. This guide covers how it actually works, the RNG process behind the variable reel heights, who owns and licenses it, and what to know about RTP and volatility across specific named titles before playing a Megaways title.

What Megaways Actually Is

Standard slots use a fixed grid — five reels, each showing a set number of symbols, with a fixed number of paylines or ways to win that never changes spin to spin. Megaways replaces that fixed structure with reels of variable height: each of the (typically six) reels can display anywhere between 2 and 7 symbols on any given spin, decided randomly each time. Because the number of symbols per reel changes, the number of possible winning combinations changes with it — which is the entire basis of the mechanic's headline feature.

The Maths Behind 117,649 Ways

This figure gets quoted constantly in Megaways marketing, and it's worth understanding exactly where it comes from rather than taking it as a vague "lots of ways to win" claim. With six reels, if every reel happens to land its maximum of 7 symbols in the same spin, the number of ways to win is 7 × 7 × 7 × 7 × 7 × 7 = 117,649. That's the ceiling — the maximum theoretically possible on a standard six-reel Megaways game, occurring only when every reel independently lands its maximum height in the same spin.

At the other end, if every reel lands its minimum of 2 symbols, the result is 2 × 2 × 2 × 2 × 2 × 2 = 64 ways — still considerably more than a standard fixed-line slot, but a fraction of the headline maximum. Most spins land somewhere between these two extremes, so the actual number of ways to win genuinely fluctuates on every spin, visible on screen as the reel heights and the ways-to-win counter both change in real time.

Some titles push the mechanic further still — variants with more reels or higher maximum symbol counts per reel have been built specifically to advertise even larger maximums. Big Time Gaming's own White Rabbit Megaways expands its reels during free spins to reach a reported 248,832 ways, while one well-known licensed title, Who Wants to Be a Millionaire Megaways, is marketed around up to 1,000,000 ways to win using an extended reel structure beyond the standard six-reel, seven-symbol Megaways template.

How the RNG Actually Decides Each Reel's Height

The variable reel heights aren't a purely cosmetic animation layered over a fixed result — each reel's symbol count for that spin is generated by the game's random number generator, independently of the other reels, before the symbols themselves are drawn from that reel's weighted symbol strip. In practice, this means the RNG runs a separate randomised process to decide "how tall is reel one this spin," "how tall is reel two," and so on, with each reel's possible heights (2 to 7 symbols) not necessarily equally likely — the underlying probability weighting is calibrated by the studio to hit the game's target RTP and volatility profile, in the same way a standard slot's symbol-weighting is calibrated, rather than every height between 2 and 7 being equally probable.

This is why the "ways to win" counter and the visible reel heights update instantly and match exactly what's shown on screen — the RNG result for reel height is generated first, then the visible symbols populate accordingly, and the ways-to-win figure is simply the product of whatever heights were generated that spin. As with any regulated slot mechanic, the RNG implementation and the resulting return-to-player figures are independently tested by accredited labs — commonly cited testing bodies in this space include eCOGRA, iTech Labs, and Gaming Laboratories International (GLI) — which run large volumes of simulated spins against the game's actual code to verify the stated RTP and confirm the reel-height distribution behaves as intended before a game is certified for a licensed market.

Cascading (Tumbling) Reels

Megaways is almost always paired with a cascading — sometimes called tumbling or avalanche — win mechanic, though the two are technically separate features often bundled together. After a winning combination lands, the symbols involved in that win are removed, and new symbols drop in to fill the gaps, all within the same paid spin. If the new symbols happen to form another winning combination, that combination pays too, and the process repeats — creating win chains from a single spin rather than requiring a fresh spin for every combination.

Different studios use different branding for functionally the same mechanic — cascading, tumbling, avalanche, and "reactions" all describe the same symbol-removal-and-replacement process layered on top of the core Megaways variable-reel structure.

Unlimited Win Multipliers

Many Megaways titles add a further layer specifically within their free spins or bonus rounds: a win multiplier that increases with each successive cascade in a chain, often with no stated cap. As long as cascades keep triggering new wins within a single spin or bonus sequence, the multiplier keeps climbing — which is a significant part of what produces Megaways slots' occasionally very large advertised maximum win potential. This uncapped structure is also exactly why bonus round outcomes on Megaways titles can vary so dramatically from one bonus trigger to the next — a short cascade chain ends with a modest multiplier, while a long one can compound into a considerably larger payout, with genuinely wide variance between the two outcomes.

Who Owns Megaways, and Who's Licensed to Use It

Big Time Gaming created and patented the Megaways mechanic, debuting it in Bonanza in 2016 — the game most commonly credited with introducing the format to the market. Because the underlying mechanic is patented, other studios can't simply copy it; Big Time Gaming licenses the Megaways mechanic to other developers, which is why the format now appears across games from studios including Pragmatic Play, Blueprint Gaming, Red Tiger, and Relax Gaming, alongside Big Time Gaming's own titles.

This licensing structure matters for one practical reason: a licensed studio's version of Megaways can carry different RTP and volatility characteristics than Big Time Gaming's own originals, even though both use the same underlying variable-reel mechanic. The mechanic itself is standardised across licensees; the specific paytable, RTP, and bonus design built around it isn't.

Reel Kingdom: A Related but Separate Brand Worth Untangling

It's worth clearing up a genuine source of confusion here, since the name sounds like it could be part of the Megaways family tree. Reel Kingdom is a games studio that partners specifically with Pragmatic Play, producing base titles — including Big Bass Bonanza and Emerald King — that Pragmatic Play then separately builds Megaways versions of under its own licence from Big Time Gaming. Reel Kingdom itself is not affiliated with Big Time Gaming and doesn't own or license the Megaways mechanic — its role is as a development partner supplying Pragmatic Play with original game concepts, some of which subsequently get a Megaways-branded spin-off release. The Megaways version of a Reel Kingdom-originated title is still, structurally, a Pragmatic Play Megaways release, licensed from Big Time Gaming in the same way as any other studio's Megaways titles — Reel Kingdom's contribution is the base game design, not the ways-to-win mechanic layered onto it afterwards.

RTP and Volatility: What to Expect

Megaways slots are almost always built as high or very high volatility games — a direct consequence of the uncapped multiplier and wide ways-to-win range covered above, which naturally produces bigger, less frequent wins rather than smaller, steadier ones. Typical RTP across Megaways titles generally falls in the 95% to 97% range, though this varies meaningfully by specific game and by which studio built it — checking the individual game's stated RTP rather than assuming a fixed Megaways-wide figure is worth doing before playing any specific title, as the named examples below illustrate.

Named Megaways Titles Compared

The spread here is informative in itself: White Rabbit Megaways' reported RTP of roughly 97.7% sits well above Bonanza's roughly 96.0%, despite both being Big Time Gaming's own titles using the identical core mechanic — a reminder that even within one studio's catalogue, RTP is set on a game-by-game basis rather than being a fixed property of the Megaways system itself.

Well-Known Megaways Titles

Bonanza — the original Big Time Gaming release that introduced the mechanic in 2016, still widely available and often used as the reference point for the format.

Extra Chilli — another widely-played Big Time Gaming Megaways original, commonly cited alongside Bonanza as a genre-defining title.

White Rabbit Megaways — a Big Time Gaming title notable for its own reel-expansion feature during free spins, pushing its maximum ways figure well beyond the standard template, alongside a reported RTP towards the top end of the Megaways range.

Big Bass Bonanza Megaways and Fishin' Frenzy Megaways — Megaways versions of two already well-established slot series covered in dedicated detail elsewhere on this site (see this site's existing Big Bass Bonanza and Fishin' Frenzy guides), applying the variable-reel mechanic to already-popular base games rather than introducing an entirely new theme.

Buffalo King Megaways — a Pragmatic Play licensed title, one of the studio's own Megaways releases (see this site's Pragmatic Play provider hub for more on the studio's wider slot range).

Who Wants to Be a Millionaire Megaways — a licensed-brand title built on an extended reel structure specifically to advertise up to 1,000,000 ways to win, beyond the standard six-reel, seven-symbol template's 117,649 ceiling.

Where to Play Megaways Slots

Megaways titles are widely available across major UK-licensed casino operators, including bet365 and Unibet, both already reviewed on this site, alongside most other UK operators carrying slots from Big Time Gaming, Pragmatic Play, and the format's other licensees. Given how widely licensed the mechanic is, availability of specific Megaways titles varies more by which slot studios a given operator carries than by whether that operator supports Megaways as a format at all.

A Practical Checklist Before Playing

Check the specific game's stated RTP rather than assuming a fixed Megaways-wide number — the range genuinely varies by title and by which studio licensed the mechanic, as the named-title comparison above shows.

Understand that high volatility is close to a defining feature of the format, not an occasional trait — expect longer stretches without a significant win, offset by the potential for larger ones when a long cascade chain lands.

Don't treat the advertised maximum ways-to-win figure as typical — 117,649 (or higher, on extended-reel variants) is the ceiling case, not the average spin; most spins land well below it.

Don't assume "Reel Kingdom" means a different mechanic — titles originating from Reel Kingdom that carry a Megaways version are still standard Pragmatic Play-built, Big Time Gaming-licensed Megaways releases underneath.

Set a session budget before starting, as with any high-volatility slot format — Megaways' variance is exactly what makes disciplined bankroll management worth being deliberate about.

Who Megaways Slots Genuinely Suit

Good fit: players who enjoy high-volatility slots and want the visual variety of reels that genuinely change shape and win-count every spin, alongside the bigger (if less frequent) win potential that comes with uncapped cascade multipliers.

Less suited: players specifically looking for steadier, more frequent smaller wins — low or medium volatility slots with fixed paylines are a better match for that playing style than the inherently high-variance Megaways format.

Frequently Asked Questions

How is 117,649 ways to win actually calculated?

It's 7 × 7 × 7 × 7 × 7 × 7 — the result of all six reels simultaneously landing their maximum of 7 symbols in a single spin. This is the ceiling case, not a typical or guaranteed outcome; the actual number of ways fluctuates every spin based on how many symbols each reel happens to land.

How does the RNG decide how tall each reel is on a given spin?

Each reel's symbol count is generated independently by the game's random number generator before the symbols themselves are drawn, with the probability of each possible height (2 to 7 symbols) weighted by the studio to hit the game's target RTP and volatility — not every height is equally likely. The result is independently tested by accredited labs before certification.

Who owns the Megaways mechanic?

Big Time Gaming, which created and patented it, debuting the format in Bonanza in 2016. Other studios — including Pragmatic Play, Blueprint Gaming, Red Tiger, and Relax Gaming — license the mechanic from Big Time Gaming to build their own Megaways titles.

Is Reel Kingdom the same company as Big Time Gaming?

No. Reel Kingdom is a studio that partners with Pragmatic Play to produce base game titles like Big Bass Bonanza; it has no affiliation with Big Time Gaming and doesn't own or license Megaways itself. Any Megaways version of a Reel Kingdom-originated game is still a Pragmatic Play release, licensed from Big Time Gaming in the standard way.

Does every Megaways slot have the same RTP?

No. RTP generally falls in the 95% to 97% range across the format, but varies by specific title and studio — White Rabbit Megaways, for example, is reported at roughly 97.7% against Bonanza's roughly 96.0%, despite both being Big Time Gaming titles using the same mechanic. Always check a specific game's stated RTP before playing.

What does "cascading" or "tumbling" mean on a Megaways slot?

After a winning combination lands, the winning symbols are removed and new ones drop in to fill the gaps, within the same paid spin. If the new symbols form another win, that pays too, and the process repeats — creating win chains from a single spin.

Are Megaways slots always high volatility?

Almost always, yes — it's close to a defining characteristic of the format, driven by the uncapped multipliers and wide ways-to-win range. If you're specifically looking for lower-volatility, steadier gameplay, a fixed-payline slot is generally a better match.

Can the ways-to-win maximum exceed 117,649?

Yes, on extended-reel variants built with more reels or higher maximum symbol counts than the standard six-reel, seven-symbol template — White Rabbit Megaways reaches a reported 248,832 ways via free-spin reel expansion, and Who Wants to Be a Millionaire Megaways is built specifically to advertise up to 1,000,000 ways using an extended structure.

This guide is for informational purposes. RTP, volatility, and specific game mechanics vary by title and by studio — always check the individual game's information screen for current, exact figures before playing. 18+ only. UKGC-licensed operators only. Gambling problem? BeGambleAware.org | National Gambling Helpline 0808 8020 133. Information correct as of September 2026.