Untap · Journal · 30 April 2026
The Forgotten Tap.
What Londoners are owed when they don’t tap out.
£164.7 million, in one year, from passengers who didn’t tap out.
In 2023, Transport for London charged passengers £164.7 million in maximum fares for journeys that ended without a proper tap-out (Source: TfL FOI-4311-2324, response dated 25 March 2024.). That figure comes from a Freedom of Information request, because TfL doesn’t publish it routinely. It is the single largest line of overcharge revenue the agency collects from ordinary passengers, and almost all of it is refundable.
The mechanic is simple. When you tap a contactless card or phone at the start of a Tube, Elizabeth line or London Overground journey but a reader fails to register the tap-out at the end, the system has no way to compute the correct fare. So it charges the maximum fare for that line, currently up to £8.90 per journey, the same as the Zone 1-2 daily cap (Source: Mayor of London, fares package 2025.). A single forgotten tap can cost as much as a full day’s commute.
The pattern repeats roughly 30.9 million times a year, by TfL’s own count.
TfL auto-corrects some of these. Just over a quarter.
Not every incomplete journey ends in a maximum-fare charge. TfL runs an algorithm that looks at your tap-in pattern and, if it can confidently infer the destination, it auto-completes the journey before you’re billed. In 2023, that algorithm caught 8.7 million of the 30.9 million slips (Source: TfL FOI-4311-2324.). About 28% of the total.
The other 72%, or 22.2 million journeys, get the maximum-fare treatment. Those are the ones the passenger has to claim back manually, on TfL’s contactless portal. There is no notification, no reminder, no nudge. The £8.90 charge sits in your bank statement next to the day’s capped amount, and you don’t notice it unless you go looking.
The cost per slip
A typical Zone 1-2 off-peak single is £3.10. The maximum fare is £8.90. The difference, £5.80 per journey, is what a successful refund hands you back. Multiply by half a dozen forgotten taps in a year and most commuters are looking at £30 to £50 they could ask for and don’t.
GLA fares 2025; TfL Pay-the-right-fare guidance
The clock
You can see your journey history online for about a year, but the refund form only accepts journeys from the last 8 weeks. Older slips can only be raised by phone with TfL customer services and rarely succeed. After the 8-week mark, the money stays with TfL.
TfL contactless refund pages
A three-month outage that erased some passengers’ records.
On 1 September 2024, TfL detected a cyber security incident that disabled contactless journey history for nearly three months. Refunds were paused. By the time the system was restored on 4 December 2024 (Source: TfL press release, 4 December 2024.), up to one million Londoners had been overcharged in the interim.
Mayor Sadiq Khan acknowledged at a London Assembly hearing that some passengers “may never be refunded” because the journey records they would need to claim against were not recoverable (Source: London Centric, December 2024.). TfL revised its year-end surplus down by £38 million, citing the cyber incident.
The standard 8-week claim window from late August 2024 has now closed for most affected journeys. Anyone who tapped during that period and noticed irregular charges should contact TfL customer services directly and reference the cyber outage. A goodwill resolution may still be possible.
Check it yourself, or let Untap do it.
The check is straightforward but tedious. Download a Payment Statement PDF from contactless.tfl.gov.uk for the last 8 weeks and look for any row marked with the yellow triangle, or labelled “to Unknown”. Each is a candidate for a refund. The portal lets you raise three online refund requests per calendar month; for higher volumes, call TfL customer services.
Untap reads the same PDF for you. Forward it through untap.money/upload and we tag every row as claimable, expired, or already auto-corrected. We don’t file the claim. That part stays yours, on TfL’s portal. We just save you the line-by-line check.
The full how-to, with screenshots and the edge cases, lives in our guide: TfL refunds, explained.
Reproduce every figure in this piece.
- TfL FOI-4311-2324 · Number of incomplete journeys and maximum-fare revenue, calendar year 2023, response dated 25 March 2024. View
- Mayor of London · Fares package 2025 announcement, including £8.90 maximum fare ceiling. Read
- TfL press release, 4 December 2024 · Contactless journey history and refunds restored after the cyber incident. Read
- London Centric · “Sadiq admits some TfL passengers may never be refunded,” December 2024. Read
- TfL refund and journey-history pages · Eight-week claim window, three claims per calendar month. Open
The Forgotten Tap is part of Untap’s research journal. All underlying data comes from TfL and the Greater London Authority. Comments and corrections to contact@untap.money.
Published 30 April 2026.