Return to player (RTP)
The share of all money staked that a game is designed to return to players across a very large number of rounds.
RTP, or return to player, is an average measured over the long run. A 96% RTP slot is built to give back $96 for each $100 staked across millions of spins. For a single session it predicts almost nothing.
Link to house edge
RTP is the house edge seen from the other side: 96% RTP equals a 4% edge. A higher RTP means you lose less on average over time.
Several versions of one slot
Plenty of slot studios ship the same title at several RTP levels, say 96%, 94% and 92%, and leave the choice to each casino. Visually the games are identical. Open the info or help screen inside the game at your casino to see the real figure; the provider's website will not tell you which version you are playing.
Cost comparison
$1,000 wagered at 96% RTP carries an expected loss of $40. Put the same $1,000 through a 92% version and the expected loss is $80, twice the price for the same play.
For provably fair originals
With originals like dice or limbo, the RTP follows directly from the payout formula and can be computed exactly from the published scheme.