What Is Expanding Symbols?
Expanding symbols are special symbols chosen during free spins that expand to cover whole reels. In plain English, what is expanding symbols in slots? It is a feature commonly associated with Book-style slots, where one symbol becomes larger across the reel area.
What are expanding symbols?
An expanding symbol is a special symbol selected for free spins. When the feature applies, that symbol expands to cover a whole reel rather than remaining in a single symbol position.
This expanding symbols meaning is useful when reading a slot’s paytable or feature description. The key point is that the symbol is not simply a standard reel symbol: it has a special role during free spins and can occupy an entire reel.
How expanding symbols work
The basic process is:
- A special symbol is chosen for the free-spin feature.
- The chosen symbol expands.
- It covers a whole reel.
- The result is shown as part of the free-spin feature.
The exact presentation can vary by slot, so the in-game information screen and paytable are the best places to check how a particular title applies the feature. The supplied definition does not list additional rules, triggers or payout conditions.
Simple example
Imagine that a Book-style slot chooses a book symbol during free spins. Instead of appearing in one position, the selected symbol expands until it covers a whole reel. That is the basic example of how expanding symbols work.
This example explains the feature without assuming extra mechanics, such as how the symbol is selected or how many reels it can cover.
Common misconceptions
Expanding symbols do not describe every large symbol or visual effect in a slot. The term refers specifically to a special symbol chosen for free spins that expands to cover whole reels.
The feature also does not, by itself, provide information about RTP, volatility, maximum win or the result of any spin. Those are separate details that should be checked in the individual game’s information screen.
Examples in popular slots
The database examples below include Book of 99, Taxi Movida and Book of Cats Megaways. Provider and RTP details are not listed in the supplied data, so check the relevant game information screen for those figures.
| Game | Provider | RTP |
|---|---|---|
| Book of 99 | Not listed | Not listed |
| Taxi Movida | Not listed | Not listed |
| Book of Cats Megaways | Not listed | Not listed |
RTP can differ between casino versions when it is available, so any quoted figure should be checked against the version being played.
Related terms
- Free spins: The feature period in which the special symbol is chosen and can expand.
- Book-style slots: Slot games associated with expanding symbols, including the examples listed above.
- Paytable: The in-game reference that explains symbols and available game information.
- Expanding symbols slots: Games that include this feature. For a wider set of definitions, visit the Glossary.
See slots with this feature: Browse Expanding Symbols slots.
FAQ
What are expanding symbols in slots?
Expanding symbols are special symbols chosen for free spins that expand to cover whole reels, as in Book-style slots.
Which slots use expanding symbols?
Examples from the database are Book of 99, Taxi Movida and Book of Cats Megaways.
How does expanding symbols work?
During free spins, a special symbol is chosen and expands to cover a whole reel. For more titles using this feature, see the expanding symbols slot list.
18+ only. Play responsibly; demos use virtual credits and no real money.