Why RTP alone cannot say whether a wagering requirement is survivable
RTP sets the house edge. Whether a balance can survive a specific playthrough requirement in expectation also depends on how much of each stake counts toward it, and the two combine into one number worth knowing before either is judged alone.
House edge is charged on every coin staked
House edge is RTP's complement: h = 1 - r. A 96% RTP is a 4% edge, and that edge is charged on every coin staked, not on a starting balance — which is why a wagering requirement, which forces many coins to be staked to clear a small credited amount, is expensive in a way a single spin is not.
The break-even multiplier is m* = c ÷ h
The edge alone does not say whether a specific requirement is survivable. Game contribution, c, is the share of each coin staked that counts toward the requirement: at full contribution every coin staked earns a coin of credited wagering, and at 20% contribution it takes five coins staked to earn one credited coin. The multiplier a balance can survive in expectation is m* = c ÷ h — the break-even multiplier — and it moves with both numbers, not with RTP alone.
Contribution moves m* by the same factor it moves the stake
At 96% RTP (h = 4%) and full contribution, m* = 1 / 0.04 = 25x: a 25x requirement is expected to consume the balance exactly, on average. Drop contribution to 20% on the same game and m* falls to 0.2 / 0.04 = 5x — the same 25x requirement is now five times past the point a balance is expected to survive. RTP did not change. Contribution did, and it moved the answer by 5x.
The same arithmetic applied to the two roulette records on this site shows the comparison running the other way. Single-zero roulette's house edge is exactly 1/37, so at full contribution m* = 37x; double-zero roulette's edge is exactly 2/38 (1/19), giving m* = 19x. The single-zero wheel — the higher-RTP game — survives nearly double the requirement the double-zero wheel does, at the same 100% contribution. Comparing two RTP figures without also comparing contribution answers a different question than the one that actually matters.
This is arithmetic, not advice — it says what a balance is expected to do on average, not what any single session will do. But it is arithmetic worth doing before comparing two offers by RTP alone: the higher-RTP game is not automatically the one a balance is more likely to survive, once a real contribution percentage is attached to it.
To see what an RTP assumption does to a wagering requirement, use the expected balance calculator. To see how widely results scatter around it, use the variance explorer.