Base game
The base game is a slot's normal mode: the paid spins you play between bonus features, where each spin costs your chosen stake. Everything else, from free spins to pick bonuses, is reached from it. How generous the base game is, compared with the features, shapes how quickly a session budget drains and how swingy the slot feels.
By the Best Slots UK team. Last checked .
Key takeaways
- The base game is every paid spin outside a bonus round or feature.
- Part of a slot's RTP comes from the base game and the rest from its features; the split varies a lot.
- Slots that pay little in the base game rely on features to reach their RTP, which makes them more volatile.
- In Great Britain the base game is the only route to a feature, because bonus buy is not offered.
- Also called
- Main game
- Costs
- Your stake on every spin
- Opposite
- Feature or bonus round
- UK stake cap
- £5 (25+), £2 (18–24)
- Min spin time (UK)
- 2.5 seconds
What the base game is
When you load a slot and press spin, you are in the base game. Each spin takes your stake, the reels land, and any wins are paid from the paytable. Features such as a free spins feature, a hold and win round or a pick-me bonus are separate modes that the base game can trigger. When they end, you return to the base game.
Many modern slots also have modifiers that work inside the base game itself: random wilds, cascades, multipliers that drop at random, or a respin when a certain symbol lands. These are part of the base game, not separate features, because you are still paying for every spin.
Base game versus features in well-known slots
The balance between base game and features varies a great deal. Here are five popular games and how they divide the action:
| Slot | Base game | Main feature |
|---|---|---|
| Starburst | Expanding wilds on the middle reels award respins; wins pay both ways | None; everything happens in the base game |
| Book of Dead | 10 paylines with the book acting as wild and scatter | Free spins with one randomly chosen expanding symbol |
| Gates of Olympus | Tumbling wins, with multiplier symbols landing at random | Free spins where multipliers carry over and build |
| Big Bass Bonanza | Line wins; fish money symbols land but aren't collected | Free spins where the fisherman wild collects fish values |
| Gonzo's Quest | Avalanche reels with a multiplier that rises on consecutive wins | Free Falls, with a higher multiplier ladder |
Starburst sits at one extreme: with no separate feature, its whole return comes from base-game spins, which is part of why it is low volatility. Big Bass Bonanza sits nearer the other end, where much of the excitement, and much of the return, waits in the free spins.
How much of the RTP comes from the base game
A slot's RTP is the total of what the base game returns and what the features return. Studios design the split deliberately, but very few publish it. An illustrative example shows why it matters. Imagine two 96% slots:
| Slot A (base-heavy) | Slot B (feature-heavy) | |
|---|---|---|
| Return from base game | 80 points | 55 points |
| Return from features | 16 points | 41 points |
| Total RTP | 96% | 96% |
| Expected base-game return on 200 spins at 20p (£40 staked) | £32 | £22 |
| Base-game shortfall the features must cover | £8 | £18 |
Both games cost the same on average over a very long run. But on Slot B, if the feature doesn't land during your 200 spins, you would expect to be about £18 down rather than £8. That gap is what players mean when they say a slot has a "tight" or "punishing" base game, and it is the core of what volatility describes.
These splits are made up for illustration. Real figures vary by game and are rarely published, though some help screens list the RTP of individual features or modes.
UK rules that shape the base game
Because bonus buy is not offered to players in Great Britain, the base game is the only way into a slot's features here. That means a feature-heavy slot can take many paid spins to reach its bonus, and the feature frequency entry explains how to estimate how many. Every one of those spins is subject to the UK stake limit of £5 for players aged 25 and over and £2 for those aged 18 to 24, takes at least 2.5 seconds, and can't be set on autoplay or turbo.
Those rules make base-game play slower and more deliberate than it used to be. At the minimum spin time, 200 base-game spins take a little over eight minutes. Our UK slot game design rules guide explains each rule and when it came in.
How to judge a slot's base game before you play
- Check the paytable: if five of the top symbol pays only a modest multiple, the base game is probably lean and the features carry the return.
- Look for base-game modifiers such as random wilds or cascades; they usually mean more frequent small wins.
- Read the volatility rating and any published hit frequency in the help screen.
- Watch a stretch of demo spins at your real stake to see how fast the balance drifts between features.
Related terms
The bonus round entry covers the modes the base game leads into, and dead spin describes the base-game spins that return nothing. For a full tour of how features plug into the base game, see slot features explained.
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Frequently asked questions
What does base game mean in slots?
The base game is a slot's standard mode, where you pay your stake for each spin and wins come straight from the paytable. It is everything you play outside a bonus round, free spins feature or other special mode. Features are triggered from the base game and return you to it when they end. Base-game modifiers such as random wilds or cascades still count as base game because you pay for each spin. Our how slots work guide gives the wider picture.
Is the base game or the bonus where slots pay most?
It depends on the game. On some slots, such as Starburst, the base game produces the whole return because there is no separate feature. On many modern high-volatility slots, a large share of the RTP is held back for free spins or other bonuses, so the base game pays relatively little between them. Studios rarely publish the exact split, but the paytable and volatility rating give strong clues. The volatility guide explains how to read them.
What is base game RTP?
It is the part of a slot's total return that comes from ordinary paid spins, leaving out the features. If a 96% game gets 60 points from the base game, you would expect about 60p back per £1 staked while no feature lands, with features making up the rest over time. Most UK help screens show only the total RTP, not the split. Some games list separate figures for optional modes. Our guide on how slot RTP is calculated covers this.
Why does the base game feel so slow on high volatility slots?
Because those games hold back much of their return for rare features, so ordinary spins pay less often and less generously. You may see long runs of dead spins and small wins below your stake between bonuses. This is a design choice, not a fault, and it is why such games need a budget that can absorb dry spells. Our guide to playing high volatility slots explains how to size stakes sensibly.
Can you skip the base game on UK slots?
No. Bonus buy, which lets players pay a lump sum to jump straight into a feature, is not offered to players in Great Britain. The only route to free spins or other bonuses is through base-game spins, each costing your normal stake and taking at least 2.5 seconds. Outside Great Britain a feature purchase often costs 100 times the stake or more in one go. See can you buy bonuses on UK slots for the background.
Do stake limits apply in the base game and features?
The UK limits of £5 per spin for players aged 25 and over and £2 for 18 to 24-year-olds apply to the stake you choose in the base game. Free spins rounds normally play at the stake that triggered them, so they inherit the same limit. A casino may also set a lower maximum while a bonus is active. The UK slot stake limits guide explains how the limits work and how sites check your age band.