Travellers in London who pay for their journeys using Mastercard’s contactless technology will be able to travel for free on selected Fridays across the Transport for London (TfL) network, in a promotion called “Fare Free Friday”.

Despite the option only being introduced on the Underground network two months ago, eight per cent of all pay-as-you-go journeys in London are now paid for by touching in and out with contactless cards.

Contactless payments have been available on London buses since December 2012.

The promotion, which is designed to encourage use of the new technology, will apply to all journeys paid for with a Mastercard contactless card on November 28th. The cost incurred will simply be refunded to the card without any requirement to register or sign up.

Fare Free Friday will also be available for those who pay with Mastercard’s “Cash on Tap” smartphone app.