Expanding symbols are special symbols in pokies that increase in size after a spin outcome has been determined. When triggered, they typically expand to cover an entire reel or a predefined area of the grid.
This article explains what expanding symbols are, how they activate, and how they fit into the overall mechanics of a pokie.
What expanding symbols are
An expanding symbol is a symbol that changes its visual size after the reels stop. Instead of occupying a single position, the symbol expands to fill multiple positions according to predefined rules.
Expanding symbols do not appear expanded initially. The expansion occurs only after the outcome is selected.
How expanding symbols are triggered
Expanding symbols activate when specific conditions are met. Common triggers include:
- A particular symbol landing on a reel
- A winning combination involving a special symbol
- Activation during a bonus feature or free spins
The trigger conditions are fixed and do not change during play.
Difference between expanding and stacked symbols
Stacked symbols are part of the reel layout and appear in multiple positions immediately when the reels stop. Expanding symbols, by contrast, modify their size after the outcome is determined.
Expansion is a visual and evaluative step that occurs after the initial result is known.
How expanding symbols affect winning combinations
When a symbol expands, it may create or enhance winning combinations by filling additional positions. The game then evaluates the expanded layout according to the payout rules.
If the expanded symbol completes a valid winning combination, the corresponding payout is awarded.
Expanding symbols and probability
Expanding symbols do not change the probability of outcomes. Their appearance rate and expansion behaviour are built into the game’s mathematical design.
The expected value of expanding symbols is included in the game’s overall return to player calculation.
Why expanding symbols feel significant
Expanding symbols often feel impactful because they visibly transform the game grid and can turn small wins into larger ones. The sudden change in layout draws attention and creates a sense of momentum.
Despite this perception, expanding symbols operate within fixed rules and probabilities.
Common misconceptions about expanding symbols
Several misunderstandings are common:
- Expanding symbols increase the chance of winning
- Expansion is triggered by previous losses
- Expanding symbols indicate a favourable machine
- Expansion changes RTP during a session
These beliefs do not reflect how expanding symbols function mechanically.
Why understanding expanding symbols matters
Understanding expanding symbols helps clarify how post-spin visual effects can alter displayed outcomes without altering how results are generated. Expansion affects payout evaluation, not outcome selection.
Recognising this distinction supports a clearer understanding of how pokies combine visual features with fixed mathematical design.
Informational disclaimer
PokiesHub Australia is an informational project. We do not operate gambling services, accept deposits, or provide access to electronic gaming machines.
This content is provided for educational purposes only and is intended to explain game mechanics in an Australian informational context.