The idea is that you pay but it gets refunded.
Read up first and don't blame me if it doesn't work for you.
Londoners and tourists are being given two days of free travel on the city’s Tube, train and bus networks as part of a Mastercard promotion.
Anyone owning one of its contactless payment cards will get a refund for journeys this Friday and again on 28 November.
The “Fare Free Fridays” will see travellers have fares totalling up to £21.80 a day refunded by Mastercard.
Scott Abrahams, the group’s head of emerging payments, said the use of contactless payments in the UK had more than tripled in the last year.
They were first rolled out across the Transport for London (TfL) network in September, allowing passengers to touch their credit or debit cards on pads instead of an Oyster.
More than 8 million “contactless” journeys have been made since the technology was introduced, Mastercard said, and the method now accounts for at least 7 per cent of payments.
The charge is the same as for an adult Oyster card, automatically capping fares for a day or week period.
The Fare Free Fridays offer will be valid between 4.30am on the affected days and 1am the following Saturday on the London Underground, buses, Overground, Docklands Light Railway, trams and most National Rail services.
It will also work on the company's Cash on Tap smartphone app.
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