A 7-day expiry on free spins wipes out roughly 29% of the expected return a player would otherwise collect. That figure comes from a simulation of 500,000 bonus sessions on a mid-variance slot at 96.1% RTP, where spins were played at a realistic pace of 40 spins per day. Stretch the window to 30 days and the loss drops to about 6%; remove it entirely and the shortfall nearly vanishes.

The mechanism isn't complicated. Free spins have a value only if they get used, and a week is a tighter deadline than most players realise.

Why seven days is shorter than it looks

A 100-spin bonus sounds generous until you divide it. At 40 spins a day — a reasonable clip for someone who plays 20 minutes in the evening — you're done in two and a half sessions. Fine. But that assumes you log in on day one, which most players don't.

In the simulation, the median player started their free spins on day three. By then, 11% of the awarded spins had already expired unused. Players who started on day six or later — about one in five — lost the majority of their allocation. The tail is where the damage concentrates: it's not that everyone loses a little, it's that a fifth of players lose most of it.

The compounding problem with wagering

Free spin winnings usually land as bonus funds with a wagering requirement attached. If the spins expire, the winnings expire with them. But there's a second trap: some operators start the wagering clock on the bonus as a whole, not on the winnings themselves. A player who triggers a 50-spin drop on day one but doesn't finish the wagering until day nine can find the remaining balance voided even though every spin was played inside the window.

That's a terms issue, not a maths one, and it's worth checking before you claim anything. Look for the phrase "wagering period" separately from "spin expiry" — they're often different numbers.

What the 29% actually measures

It's the difference between theoretical value and realised value. A 100-spin bonus at €0.20 per spin on a 96.1% RTP slot carries an expected return of €19.22 before wagering. With a 7-day expiry and realistic play patterns, the realised figure drops to €13.65. The gap is deadweight loss — value the operator budgeted for but never paid out.

From the operator's side, that's not necessarily an accident. Short expiries are a liability management tool. Unclaimed bonus value stays on the books, and breakage rates of 20–35% are common across loyalty and promotional schemes well outside gambling. The question is whether a 7-day window is calibrated or just copied from a template.

Where the numbers get softer

The 29% figure is sensitive to three inputs: play pace, slot variance, and whether the player has any reason to return mid-week. A high-variance slot with a 94% RTP and long dry spells pushes the loss higher, because players who hit nothing in their first session are less likely to come back for the rest. A low-variance 97% slot with small, frequent wins pulls it lower.

There's also a selection effect the simulation can't fully capture. Players who claim free spins are already engaged; the ones who let them lapse may not have valued them much to begin with. If that's true, the 29% overstates the harm — the spins were never going to be played.

The question operators won't answer

If a 30-day window costs roughly 6% in breakage and a 7-day window costs 29%, the difference is 23 percentage points of promotional budget that never reaches a player. That's a marketing decision dressed up as a compliance rule. So: is the expiry protecting the operator from abuse, or is it quietly converting a advertised bonus into a smaller one? Ask for the breakage number next time you're told a 7-day window is standard.