Casino Deposit Bonus EV Calculator

How a deposit bonus is valued

A deposit bonus normally starts with two amounts: your cash deposit and the promotional bonus. The headline bonus is not the same as expected profit because the offer may require a large amount of qualifying wagering before the resulting balance can be withdrawn.

The calculator models the starting cash, bonus, wagering amount, game RTP, stake and—when slots are selected—the volatility setting. It can also model bonus-first play and a maximum-winnings cap. Those details matter because two offers with the same bonus percentage can produce very different expected results.

Worked deposit-bonus EV example

Suppose you deposit £100, receive a £100 bonus, and must wager £1,000 on a game modelled at 95% RTP. Ignoring caps and path-dependent rules, the underlying game has a 5% house edge, so the expected cost of £1,000 wagering is £50.

The £100 deposit is not counted as profit; it is your starting cash. In this simple deterministic example the promotion adds £100 of value and the wagering consumes £50 of it on average, leaving an EV of +£50. A simulation can still finish very differently because individual spins or hands do not return exactly 95% each time.

Reproducible simulator result

This is a real output from the current simulator engine, not a hand-calculated estimate. It uses 100,000 simulations with fixed seed 20261010, generated on 10 October 2026, so the run can be reproduced from the source package.

Here the Simulated EV is higher than Mathematical EV because many trials exhaust the playable bankroll before all £1,000 of wagering is completed. The simulation therefore averages only £819.16 of actual turnover. That is exactly the kind of finite-bankroll effect the simple £100 − £50 calculation cannot represent.

Slot results use the simulator's generic payout table for the selected volatility setting, not data from a specific slot. A normal live run uses a fresh random seed, so its result will vary slightly around this published snapshot.

Open this calculator Enter the published settings above to compare a fresh live run.

Why stake size and bankroll survival matter

A simple formula assumes the full wagering requirement is completed. Real play may not get that far. If the available balance falls below the stake, the simulation stops because another bet cannot be placed. That is why a playable offer can have a different Simulated EV from the headline Mathematical EV.

Stake size is especially important relative to the bankroll. Betting £1 from a £200 starting balance gives the model many more chances to absorb normal variance than betting £50 from the same balance. The RTP has not changed, but the probability of reaching the end of the wagering requirement has.

Slot volatility changes the payout distribution rather than the stated RTP. A higher-volatility model can create larger swings and therefore a different completion or bust profile even when the long-run return target is identical.

Mathematical EV versus Simulated EV

For a straightforward deposit bonus, Mathematical EV uses the entered RTP as an exact long-run return. The calculator can withhold Mathematical EV when that deterministic path is not a reliable representation—for example, when a maximum-winnings cap makes the outcome path-dependent or when the modelled balance would not survive the full wagering requirement even under exact RTP.

Simulated EV instead plays the offer repeatedly using the selected outcome distribution. Read it alongside Bust, Completion, Avg wagered and Avg time. A positive EV with a very low completion rate is a different proposition from an offer with the same EV that completes reliably.

Common deposit-bonus mistakes

• Treating the bonus as guaranteed profit. Wagering costs and bust risk still have to be paid.
• Using the bonus multiplier instead of the actual wagering amount. Enter the turnover required by the terms.
• Ignoring game RTP variants. The same game can sometimes be offered at different RTP settings.
• Ignoring maximum winnings. A cap can materially reduce the value of high-upside paths.
• Assuming stake cannot affect EV. It may not change simple RTP cost, but it can change survival and completion in a finite-bankroll simulation.