After months of eager anticipation, Pay As You Go has pulled into Welwyn Garden City, Hatfield and Welham Green stations today.
The contactless card or smartphone payment generally offers cheaper single fares towards London, but these price caps will only be introduced at our stations next year.
However the work by Govia Thameslink Railway (GTR), parent company of Great Northern, Transport for London and the Department for Transport (DfT) to extend the contactless system - in addition to the Key Smartcard, KeyGo and paper tickets - should make going into London easier for irregular travellers.
Thameslink and Great Northern managing director Tom Moran said: "The arrival of Pay As You Go with contactless at WGC, Hatfield and Welham Green marks the completion of this year's ambitious roll-out project, which has seen 13 stations on the GTR network welcome the convenient payment method.
"We have worked closely with the Department for Transport and Transport for London to bring contactless to our stations, giving customers greater choice and generally lower single fares."
Shashi Verma, chief technology officer at Transport for London, said: "It is great that we have been able to work with Govia Thameslink Railway to complete the latest expansion of pay as you go with contactless on their services.
"Almost 25 million journeys in and around London are now made using contactless every week, making travel more convenient and accessible for all."
Mike Guerra, of Welham Green Rail Users Group, said: "I am pleased that it will now be possible to obtain just-in-time ticketless access for rail journeys into London without having to queue for tickets at a busy ticket vending machine.
"For passengers used to TfL's pay as you go system where contactless card use is becoming the norm, this is an important step, perhaps looking forward to a time when ticketless travel will be the norm across the national transport system."
For more information and advice on the use of contactless and the cheapest payment for you, visit thameslinkrailway.com/tickets/oyster-contactless-and-plusbus/contactless-travel.
Customers using contactless payment cards can create an online account here contactless.tfl.gov.uk.
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