That’s a surprisingly common occurrence! There are several likely reasons why a bus might only charge you 10p:
Capping / Daily Price Cap: Most modern contactless systems have a daily or weekly fare cap. If you’ve already made several journeys that day, the 10p could be a final “settlement” charge to bring you up to the exact capped amount. For example, if the daily cap is £5.00 and your previous journeys totaled £4.90, the last journey would charge just 10p.
“One More Journey” on a Weekly Cap: Similar to above, but on a weekly cap (like London’s weekly “Oyster/Contactless” cap). The system calculates that this journey takes you to the exact capped price for the week.
Pre-authorisation (“Card Check”) Charge: Some systems initially place a small “hold” or pre-authorisation charge (often £1 or less) when you first tap in to check the card is valid. This is then replaced by the full fare later. You might have seen the 10p pre-auth before the full fare was taken. Check your bank statement again after 24-48 hours to see if the correct full fare was deducted separately.
Short Hop or Zone Change: In some areas with zonal fares, a very short journey that crosses just a small part of a zone might have a minimal fare. A 10p charge could also be an adjustment for entering/exiting a specific zone boundary.
Concession or Discount Applied: If you have an automatic discount linked to your contactless card (like a young