Return to player is a theoretical, long-run measure for a defined rules configuration. It does not predict a single session or guarantee a return. Different releases can use different settings. Read the exact rules and avoid assuming that a figure from another edition applies.
Keep a useful record
Save the title, provider and rules version together. Treat unconfirmed details as unknown, and revisit the source when a release changes.
Put the context to use: browse profiles ↗