A 31% fall in payment disputes on £20 slot top-ups made after 10pm is the headline figure from a twelve-month study of pay-by-bank rails at three mid-sized UK-licensed operators, and it is a bigger number than the industry expected. The data, covering roughly 4.1 million deposits between March 2024 and February 2025, suggests the argument for open banking in iGaming has quietly shifted from cost-per-transaction to dispute reduction. Late-night, low-value top-ups — historically the messiest corner of the deposit book — are where the effect is strongest.

That matters more than it first appears. A £20 deposit is not a commercial event for most operators; it is a fraud and chargeback event. The economics of small stakes are dominated by the cost of getting them wrong.

Why £20 at 10pm is the worst case in the deposit book

A £20 slot top-up at 10pm sits at the intersection of four problems. The amount is small enough that card schemes treat it as low priority for fraud tooling but large enough to trigger a chargeback when it is disputed. The hour means fewer customers are willing to sit on hold to a call centre, so disputes escalate rather than resolve. The product — slots — has a high ratio of transactions to session length, so a single frustrated customer can generate several disputed deposits in one night. And the customer is often mid-session, which means the deposit is time-critical and abandoned attempts convert into complaints rather than retries.

Card disputes on deposits of this size typically resolve in one of three ways: the operator refunds to avoid the chargeback fee, the scheme rules in the customer's favour, or the case drags on and the customer churns. None of these is cheap. A single chargeback on a £20 deposit can cost an operator £15–£25 in fees and admin before any refund is considered, which means the dispute is worth more than the deposit.

The study's 31% reduction applies specifically to disputes raised within 72 hours of a £20–£25 deposit made between 22:00 and 02:00. It does not apply to all deposits, and the operators involved were careful to say so. On daytime deposits of the same value, the reduction was 9%. On deposits above £100, it was 4% and not statistically significant across the sample. The effect is concentrated exactly where the pain was.

What pay-by-bank actually changes

The mechanism is less about fraud prevention than about certainty. A card deposit can be authorised, appear as successful, and still be reversed weeks later under scheme chargeback rules. A pay-by-bank transfer is an account-to-account push payment: once the funds settle, they settle. The customer's own bank has authenticated them via their banking app, which means the "I didn't authorise this" dispute route is largely closed off.

That closure is the whole point. The most common late-night dispute pattern is not organised fraud — it is regret, confusion, or a third party using the account. A £20 slot top-up at 10pm is frequently a customer who was drinking, or a partner who found the transaction on a shared statement. Under card rules, both can produce a chargeback. Under pay-by-bank, the customer's bank has a record of biometric or app-based authentication at the moment of payment, and the dispute is far harder to sustain.

Operators in the study reported that the biggest single driver of the reduction was not fewer attempted disputes but fewer successful ones. Customers still complained. They just stopped winning.

The numbers behind the headline

Across the three operators, the sample broke down as follows. Total deposits in the £20–£25 band between 22:00 and 02:00: 612,000. Of those, 41% were card, 38% pay-by-bank, and the remainder a mix of e-wallets and vouchers. Disputes per 10,000 deposits ran at 47 for card and 32 for pay-by-bank over the full period, but the gap widened sharply in the final six months as pay-by-bank adoption among late-night users rose from 31% to 44%.

The 31% figure is a like-for-like comparison within the same operators, same value band, same time window, controlling for customer tenure and prior dispute history. It is not a comparison against operators who do not offer pay-by-bank, which would have introduced too many variables.

One caveat worth stating plainly: the study was funded by a payments provider with a commercial interest in open banking. The methodology was reviewed independently, and the raw data was shared with two of the operators' compliance teams, but the framing is not neutral. Treat the 31% as a credible directional figure rather than a precise constant.

The cost side

Pay-by-bank is not free. Typical UK pricing for iGaming merchants runs at 0.4%–0.9% per transaction, against 0.9%–1.8% all-in for card once interchange, scheme fees, and fraud losses are included. On a £20 deposit, that is a saving of roughly 10p–18p per transaction — trivial in isolation, meaningful at 612,000 transactions.

But the dispute reduction is where the real money sits. If a chargeback costs £20 all-in and the dispute rate falls from 47 to 32 per 10,000 deposits, the saving is 15 disputes per 10,000 deposits, or £300 per 10,000. On the late-night £20 band alone, that is roughly £18,400 across the sample period for the average operator. Add the reduction in customer service time and the lower churn among customers who would otherwise have had a deposit reversed, and the case strengthens further.

None of this is transformative at operator scale. It is a margin improvement, not a strategy. But margin improvements of this kind compound, and the compliance benefit — fewer chargebacks means fewer scheme warnings and a lower risk of losing card acquiring entirely — is harder to price.

What the FCA and PSR have said

The Payment Systems Regulator has been pushing open banking as a cheaper, more secure alternative to card for low-value transactions since 2023, and its 2024 report on authorised push payment fraud noted that account-to-account payments carry different dispute characteristics to card. The FCA's consumer duty rules, in force since July 2023, require operators to demonstrate that payment methods are appropriate for the customer's circumstances. A £20 late-night top-up via card, with its chargeback exposure and slower settlement, is a harder position to defend than the same deposit via pay-by-bank.

There is a tension here. Pay-by-bank reduces a customer's ability to dispute a transaction. That is good for operators and arguably good for fraud prevention, but it is not unambiguously good for consumers. A customer who genuinely did not authorise a payment has fewer routes to redress under account-to-account than under card. The PSR has acknowledged this and is consulting on a reimbursement framework for open banking payments, but nothing is in force yet.

For now, the balance sits with the operator. Offering pay-by-bank as the default for small late-night deposits, while keeping card available for larger amounts and for customers who prefer it, is a defensible position under consumer duty. Making it the only option is not.

Where this leaves the late-night deposit

The interesting question is not whether pay-by-bank reduces disputes — the evidence says it does, at least for small late-night deposits — but whether that reduction reflects better payment infrastructure or a shift in who bears the risk. If the 31% fall is mostly customers losing disputes they would previously have won, the industry has not solved a problem; it has moved it.

That distinction will matter when the PSR's reimbursement rules land. Operators building their late-night deposit strategy around pay-by-bank should be modelling two scenarios: one where open banking disputes remain hard to win, and one where they become as easy as card. The 31% figure holds in the first. In the second, it is a number worth checking again.