More than 55,000 penalty charges remain unpaid from December after drivers failed to pay the Dart Charge at the Dartford Crossing.
Over 18,000 foreign drivers are being chased by a European debt recovery agency after failing to make payment.
The Highways Agency said that more than 90% of chargeable journeys made at the Crossing during December have now been paid for.
130,306 penalty charge notices have been sent to drivers who used the crossing in December without paying, which has resulted in a further 73,898 payments being received. First time contraventions include an offer of an extra 14 days to pay the crossing charge without penalty.
Highways Agency project director Nigel Gray said: “These figures show drivers are getting to know and understand Dart Charge, and is that our approach of offering drivers an extended period to pay any vehicle’s first crossing charge is getting the right results. The vast majority of drivers are paying Dart Charge and each day this continues to rise.
“It’s great that well over half a million drivers have registered for a Dart Charge account and are benefitting from discounted crossings. This means that in many cases drivers are paying less to use the Crossing now than before Dart Charge was introduced. I urge anyone who uses the Crossing more than a couple of times a year to sign up for an account and benefit from savings.”
Dart Charge was introduced on 30 November 2014 to help speed up journeys at the Dartford Crossing by removing the need to stop at a barrier to pay the crossing charge. Instead, drivers can pay online, by phone or at one of thousands of retail outlets nationwide.
However, according to a BBC report some users of the Crossing have experienced problems with the new system. Complaints have centred around delays and failures of the computerised system for setting up accounts to pay the new Dart Charge.
Gray admitted that the Agency had been “experiencing teething problems” and told the BBC: “The scheme is delivering significant benefits to most drivers. We are dealing with up to 140,000 crossings a day so it would be most surprising if we didn't get some hiccups.
"We are working really hard to try and improve the service but it is still very early days for us."