A survey of 2,140 UK online casino and sportsbook customers, run for this publication by a market research panel in February 2025, found that 27% had abandoned a session entirely when asked to complete identity or source-of-funds checks mid-play. The behaviour clustered late: 41% of those abandonments happened between midnight and 3am, with 1am the single busiest hour. The finding matters less as a complaint about friction than as a measurement of what happens when compliance meets a player who is tired, mildly intoxicated, and holding a balance they can no longer touch.

What the data actually shows

The headline 27% needs unpacking, because "abandoned a session" covers several different behaviours. Of the 578 respondents who said they had quit mid-check, 63% said they closed the site and did not return that night; 22% said they returned within 48 hours and completed the check; and 15% said they had not returned at all, in some cases weeks later. That last group is the commercially interesting one, and also the one with the most ambiguous welfare reading.

Timing was the sharpest signal. Requests arriving between 22:00 and 03:00 were far more likely to trigger abandonment than the same request at 14:00 — 41% of reported walkaways fell in that five-hour window, against a base rate of roughly 21% for that period in the sample's overall play-time distribution. The gap survives controlling for stake size and game type, though self-reported data of this kind is always softer than operator-side logs would be.

The checks themselves were not uniform. Age and identity verification, usually automated and near-instant, rarely caused abandonment — 8% of the walkaway group cited them. Source-of-funds requests, which demand documents and a narrative, accounted for 54%. Enhanced due diligence under the Money Laundering Regulations 2017, triggered by deposit thresholds or risk scoring, accounted for most of the remainder. In other words, the 27% figure is really a figure about document requests, not about KYC in general.

Why 1am specifically

Late-night players are a distinct population. They are more likely to be playing on mobile, more likely to be chasing losses, and less likely to have the paperwork to hand. A request for three months of bank statements at 1am is not a neutral compliance act; it is an instruction to stop playing and go and find a PDF. The practical response — close the app, deal with it tomorrow — is rational, and the fact that only 22% came back within two days suggests "tomorrow" often does not arrive.

There is a welfare dimension here that operators rarely discuss openly. A forced break at 1am is, functionally, a cooling-off period delivered at the moment a player is most likely to be making poor decisions. Some responsible-gambling teams have started to notice this: the check that frustrates the punter is also the check that interrupts a chasing session. Whether that is a happy accident or an argument for scheduled late-night verification is a question the industry has not settled.

The commercial arithmetic operators are running

Against that sits the commercial reality. A mid-session check on a depositing customer is expensive: support time, document review, and the risk that the customer simply leaves. Operators have historically managed this by front-loading verification — verifying at sign-up and first deposit, when the customer expects it, rather than at 1am on a Tuesday.

The numbers explain the reluctance to interrupt. In our sample, the median balance held by players at the moment of an abandoned check was £84. That money stays on the account, but the player does not. If a typical late-night session generates £30–£60 in net gaming revenue per active customer, and a check costs perhaps £4–£7 in manual review, the calculation is not about the cost of the check — it is about the lifetime value of a customer who feels ambushed.

The Gambling Commission's position has been consistent: verification should happen before gambling, not during it, wherever practicable. The 2019 guidance and the subsequent 2022 tightening of remote customer interaction requirements both push towards pre-deposit checks and away from mid-session interruption. Operators who still trigger document requests mid-play are, in the regulator's framing, doing KYC badly rather than doing it thoroughly. The 27% figure is therefore partly a measure of poor implementation, not an inevitable cost of compliance.

What good looks like, and why it is hard

The operators getting this right tend to share three features. First, they verify identity and age at registration using credit reference and electoral roll data, so the automated checks never surface to the player. Second, they set source-of-funds thresholds in advance — commonly £2,000 in a 90-day window, though some use £500 per month for higher-risk cohorts — and communicate them at sign-up rather than at the point of breach. Third, they route late-night triggers to a queued review rather than an immediate demand, allowing the player to finish the session within a capped deposit limit while the documents are processed.

That third measure is where the regulatory tension sits. Deferring a check is a judgement call, and if the deferral is wrong, the operator has allowed a session it should have stopped. The Commission has been clear that deferral must be risk-based and documented, not a blanket policy to protect revenue. A few large operators now run what amounts to a triage: automated checks in real time, a soft prompt for documents with a 24-hour grace period for low-risk players, and an immediate hard stop only where risk scoring is high.

The mobile problem

One under-discussed factor is device. 78% of the abandoned sessions in our sample were on mobile. Uploading a bank statement or photographing a payslip on a phone at 1am is a materially worse experience than doing it on a laptop, and the drop-off reflects that. Operators who have invested in in-app document capture with instant validation — rather than an email link to a web form — report noticeably lower abandonment. It is an unglamorous fix, but the data suggests it is worth more than most retention campaigns.

The question nobody wants to ask

The uncomfortable implication is that a meaningful share of late-night mid-session checks are doing harm and good at the same time, and the industry has no shared method for telling which is which. A player who walks away at 1am because they cannot produce a payslip may be a lost customer, or may be someone who needed to be stopped. The 27% figure does not distinguish between those two people, and neither, currently, does any operator's reporting.

What would change that is better data: operator-side logs matched to player outcomes, rather than self-reported surveys like this one. Until then, the working assumption should be that mid-session checks are a failure of design, not a feature of compliance — and that the 1am walkaway is a symptom worth measuring properly, if only because the alternative is guessing at how many of those players were being protected and how many were simply being inconvenienced out of the door.

If you are being asked for documents you cannot immediately provide, GamCare (0808 8020 133) can talk through options, including how to request a temporary account block while you sort them out.