Cashback and free spins are the two most common casino bonus types, and on the surface both sound equally generous: 'get some money back' or 'spin for free.' But once you run the actual ROI math, they're fundamentally different tools — and one of them is almost always the better deal, depending on the terms attached.
What is a cashback bonus and how is it calculated?
Cashback returns a percentage of a player's net losses over a set period, usually a week or a month. Typical rates run 5-15% of net loss, often capped at €50-200 per cycle. The key difference from most other bonuses is a low wagering requirement on the cashback itself — usually 1x-5x, sometimes none at all. That means cashback converts almost directly into real, withdrawable balance instead of triggering another round of playthrough.
What are free spins and what's their hidden cost?
Free spins are pre-paid rounds on a specific slot, with the casino covering the stake. A package of 50 spins at €0.20 each looks like '€10 for free,' but winnings from free spins almost always land as bonus balance with a 30x-45x wagering requirement, not cash. That multiplier is the hidden cost — it eats up most of the nominal value long before a player sees a single cent become withdrawable.
How do you calculate the real ROI of free spins?
Take 50 free spins at €0.20 = €10 in nominal stake value. At a 96% RTP slot, the expected win from those spins is roughly €9.60. Then the wagering requirement kicks in: if the terms demand 40x on that win, you need to turn over €9.60 × 40 = €384 before the money becomes withdrawable. On every bet inside that turnover, the house keeps the same 4% edge (100% − RTP), so the expected loss while clearing the requirement is €384 × 4% = €15.36. Net expected outcome: €9.60 − €15.36 = minus €5.76. On average, across a large enough sample of players, a high-wagering free spins package is statistically a loser — even though the spins themselves were 'free.'
How do you calculate the real ROI of cashback?
Say a player loses €150 in a week, and the casino refunds 10% of net loss as cashback, capped at €100. That's €15 in cashback. If the wagering requirement on the cashback is 1x — standard at many operators — the player only needs to turn over that €15 once, and the expected loss on that single pass is €15 × 4% = €0.60. Real expected value of the cashback: €15 − €0.60 = €14.40, meaning the player keeps around 96% of the nominal amount. The gap versus free spins is obvious: the lower the wagering relative to the bonus amount, the closer the real ROI gets to the number printed on the promo banner.
How do you compare cashback and free spins in 5 steps?
- Find the wagering requirement for each bonus in the T&Cs — look for 'wagering requirement' or 'rollover' next to a percentage or multiplier.
- Multiply the nominal bonus value (cashback amount, or the expected win from free spins) by that wagering multiplier — that's the real turnover you have to generate.
- Multiply that turnover by the game's house edge (100% minus RTP) — this gives you the expected loss while clearing the requirement.
- Subtract the expected loss from the nominal bonus value — that's the real ROI in actual money, not the marketing percentage.
- Compare the final numbers for both bonus types and pick whichever has the higher real ROI, not whichever sounds more generous on the banner.
When are free spins actually better than cashback?
Free spins win only in a narrow case: low wagering (1x-10x) combined with a high-RTP slot (97%+) — there, nominal and real value almost match, and the bonus genuinely feels free. Cashback tends to win for regular players riding normal variance, since it systematically lowers your effective house edge by 5-15 percentage points, while high-wagering free spins often just repackage extra playthrough as a gift. Before activating either type, it's worth running the 30-second wagering calculation using the same formula.
What terms should you check before picking a bonus?
- Wagering above 35x on free spins or above 10x on cashback — a sign the bonus exists for marketing, not real value.
- A cashback cap under €20-30 per week — at regular play volume, the payout becomes symbolic.
- A capped max bet during wagering (often €5) — exceed it and the casino can void the entire win.
- A bonus validity window shorter than 7 days — not enough time to clear the requirement without rushing into extra risk.
- No explicit list of eligible slots with 100% wagering contribution in the T&Cs — different games count differently, from 100% down to 0%.
Both bonus types are offered legally by MGA- and UKGC-licensed operators, including LeoVegas and Betway — but wagering terms and cashback caps vary from casino to casino, so compare them using the formula above rather than the headline number. Current offers of both types are listed in our [bonus directory](/bonuses) before you decide what to claim at a specific casino.