on which PAYG can be used. This meant it was possible for a passenger to board a Stansted Express train having entered the station using their card and then travel to Stansted Airport, where they would be charged a penalty for travelling without a valid ticket. This led to some accusations that Stansted Express was operating a scam, by penalising passengers who were unaware that they had done anything wrong; in 2019, it was reported that the number of penalty charges issued at Stansted Airport was 16,000 per year.

In March 2026, after