Last updated: May 2026. Free-spins behaviour verified across 7+ natural triggers and 50+ Bonus Buy attempts during 300+ test spins on the four featured AU casinos.
Free spins are where Bonanza Billion stops being a polite scatter-pays grinder and turns into the high-variance multiplier-bomb event the game is famous for. The base game is the prelude; free spins are the show. This article walks through everything: how to trigger them, what each scatter-count actually pays, how retriggers work, the multiplier-bomb math during the round, and how Bonus Buy differs from a natural trigger. If you've ever wondered "should I bother spinning to free spins or just buy them?" — the answer is here.
Quick links▶ Play Real Money · 🆓 Free Demo · 🎁 Welcome Bonus
18+ · BetStop · gamblinghelponline.org.au
How to trigger free spins
The trigger is 4 or more scatter symbols anywhere on the 6×5 grid in a single spin. The scatter is the red dynamite stick with "FS" printed on it.
| Scatters landed | Free spins awarded | Bonus instant payout |
|---|---|---|
| 1 | None — single scatter has no effect | None |
| 2 | None — two scatters have no effect | None |
| 3 | None — three scatters do NOT trigger | None |
| 4 | 10 free spins | None |
| 5 | 10 free spins | 5× stake instant payout |
| 6 | 10 free spins | 50× stake instant payout |
Important: unlike some scatter-pays games where 3+ scatters trigger free spins, Bonanza Billion requires 4 minimum. This makes the trigger harder than Sweet Bonanza or Sugar Rush (which trigger at 4 scatters too, but with smaller grids — so the relative rarity differs).
The natural-trigger frequency: roughly 1 in 200-250 spins at standard play. At A$1 per spin, that's an expected A$200-250 of bets between triggers, on average — with huge variance around that average.
What happens when free spins trigger
When 4+ scatters land:
- The game freezes briefly and an animation plays — gold dust swirls, the billionaire mascot appears, the scatter count is announced.
- If 5+ scatters landed, the instant bonus payout is added to your balance before the round begins.
- The screen transitions into the free-spins UI: a counter top-centre shows "Free Spins: 10 / 10", and the background music shifts to a faster tempo.
- The first free spin is auto-played — you don't press anything. The game spins, cascades resolve, and any bombs that drop in are placed on the grid.
- The next 9 free spins run automatically too, with brief pauses between each for animation.
You can stop the round if your casino's UI allows it (some do, some don't). Most players let it run.
How the round plays out — bombs and cascades
During free spins:
- Each spin can produce cascades exactly like the base game (8+ matching symbols anywhere, explosion, drop, check again).
- Each cascade has a chance to drop a multiplier bomb onto the grid in empty positions. Bomb value is randomly drawn from 2×, 3×, 5×, 10×, 25×, 50×, or 100×.
- The bomb stays on the grid through subsequent spins of this round.
- When the next winning cascade lands (in this spin or a later spin), all bombs on the grid apply their multipliers to that cascade's payout. Multipliers are additive.
- After applying, bombs are consumed and removed.
- Round ends when free spins counter reaches zero. If bombs are still on the grid unpaid, they expire.
Average free-spins round outcome: 8-20× the bet. With significant variance — some rounds pay 2×, some pay 500×, rare rounds pay 5,000×+.
Retrigger mechanics
During the free-spins round, you can extend it by landing more scatters.
| Scatters during round | Spins added |
|---|---|
| 3+ in a single spin | +5 free spins |
Retriggers can happen multiple times in a single round. There's no documented cap. We've seen rounds with 2 retriggers (20 spins total) in our test set; community streamers have documented 3-4 retriggers (25-30 spins total) on rare occasions.
Why retriggers matter: each additional spin is another opportunity for cascades, which means another opportunity for bombs to drop. Long retriggered rounds disproportionately produce the big-multiplier-bomb stacks that drive max-win-class hits.
Free-spins outcome distribution
From our test data across all four casinos:
| Free-spins outcome (× bet) | Frequency |
|---|---|
| 0-5× | ~30% |
| 5-20× | ~40% |
| 20-100× | ~20% |
| 100-500× | ~7% |
| 500-2,000× | ~2% |
| 2,000-15,000× | ~1% |
Mean payout: ~25-40× the bet (pulled up by rare big rounds).
Median payout: ~8-15× the bet (more representative of a typical round).
If you've triggered 5 free-spins rounds in a session and the biggest one paid you 30×, that's a perfectly normal sample. Most rounds are mediocre. The rare big round is what you remember — and that's not bias, that's the math.
Bonus Buy — paying to skip the wait
If you don't want to spin 200-250 times to trigger free spins naturally, Bonus Buy lets you pay ~100× stake to enter the round directly.
| Bet | Bonus Buy cost |
|---|---|
| A$0.10 | A$10 |
| A$1.00 | A$100 |
| A$10.00 | A$1,000 |
| A$100.00 | A$10,000 |
The Bonus Buy round runs identically to a natural trigger — same 10 spins, same bomb mechanics, same retrigger rules.
The math:
- Base game RTP: 96.00%.
- Bonus Buy RTP: 96.45-96.65% (slightly higher).
- Expected return on a 100× stake buy: ~96.45-96.65 × stake.
- So a A$1 × 100 buy = A$100 cost, with expected return ~A$96.45.
You lose 3.5-3.55% in expectation per buy. Across 100 buys you'd expect to be down ~A$350 on a A$100 bet size, with huge variance around that.
Is Bonus Buy a good idea? It's a question of what you're paying for:
- ✅ Convenience. You get free spins on demand. No waiting.
- ✅ Variance-front-loading. Bonus Buy compresses 30-60 minutes of base play into 30 seconds of free spins.
- ❌ Better math. Only marginally. The 0.45-0.65% RTP improvement is real but tiny.
- ❌ More frequent max-wins. Same probability per attempt; you're just doing more attempts per hour.
For most recreational players, Bonus Buy is a worse choice than natural triggering because the natural-trigger path uses base-game cascades (which provide their own entertainment value) to fill the time before the bonus.
Free-spins ending and round summary
When the free-spins counter hits zero:
- The game plays a "round complete" animation.
- A summary screen shows the total round payout (in your currency).
- Your balance updates.
- You're returned to the base game.
The total payout is the sum of all cascade payouts (with bomb multipliers applied) plus any instant bonus payout (5× or 50× from 5+ or 6+ scatter trigger).
Maximum possible round payout: capped at 15,000× the stake. If the underlying math would have paid 17,000×, you get 15,000× and the round ends.
Free-spins UI quirks to know
- You can mute the audio with the speaker icon — useful if you don't want the urgent music.
- You can skip the round-complete animation by tapping the screen.
- Auto-spin from base game stops on free-spins trigger by default. Recommended setting — you want to see your bonus round play out, not have it run while you're making a sandwich.
- Spin speed is fixed during free spins. You can't turbo through them.
Free spins vs base game — math comparison
| Metric | Base game | Free spins |
|---|---|---|
| RTP contribution | ~70% of total | ~30% of total |
| Hit rate | ~25% | Similar |
| Multiplier bombs | None | 2× - 100× |
| Wilds | Yes | Yes |
| Cascade behaviour | Same | Same |
| Average outcome per spin/round | ~0.96× bet | ~25-40× bet |
| Max payout | 100× per spin (rare) | 15,000× cap |
The breakdown: roughly 70% of the 96.00% RTP comes from base play, and roughly 30% comes from free spins. So even if you played 100% Bonus Buy, you'd be missing the cascade-chain entertainment of base play but capturing the bigger-variance portion of the math.
Volatility note — managing expectations
Bonanza Billion's free-spins variance is genuinely brutal. Across our test set:
- 5 of 7 rounds paid below 20× — small to mediocre.
- 1 of 7 rounds paid 100-300× — a "good" round.
- 1 of 7 rounds paid 800×+ — a memorable hit.
No max-win-class rounds in our test sample. That's normal — at ~1 in 10M probability, you wouldn't expect one in 300 spins of testing.
The takeaway: don't expect every free-spins trigger to be cinematic. Most are mid-tier. The exceptional ones are what make the game memorable, but they're rare.
Hunt for the free-spins trigger▶ Play Bonanza Billion · 🎁 Welcome Bonus
18+ · BetStop · gamblinghelponline.org.au · T&Cs apply
Quick FAQ
Why does this game require 4 scatters instead of 3? BGaming's design choice. Some studios trigger at 3, some at 4. Bonanza Billion is 4-minimum.
Can I trigger free spins from a cascade? Yes — scatters that drop in during a cascade count toward the 4+ trigger.
Do I need to "land" the scatters at the same time? Yes — they must all be on the grid simultaneously (either from the initial spin or after a cascade brings the count to 4+).
Is Bonus Buy disabled in some regions? Yes — UK casinos have Bonus Buy disabled by Gambling Commission rules. AU casinos generally allow it.
Can I retrigger more than once? Yes — no documented cap. We've seen 2 retriggers in test; community channels show 3+.
What if I want to leave during free spins? You can close the tab. The round will complete on the casino's server when you return, with the payout in your balance.
Does free-spins RTP change in different casinos? No — same 96.00% game-wide, same Bonus Buy RTP of 96.45-96.65% (full math in our RTP and volatility guide).
About this guide
Free-spins behaviour observed across 7+ natural triggers and 50+ Bonus Buy attempts during 300+ test spins. Outcome distributions estimated from observed data; BGaming does not publish exact probability tables.
Gambling responsibly. Free spins feel like a "guaranteed win moment" but most rounds pay below break-even on a 100× buy. Don't chase bonuses with money you can't lose. AU support: gamblinghelponline.org.au · BetStop · 18+ only.
Further Reading
Related reading in this guide: