Oyster cards and contactless payment cards are valid for travel to and from Stratford International, with the DLR station in Travelcard zone 2/3, but special fares apply at the HS1 station.
Stratford and several other stations have been moved from Zone 3 to the new Zone 2/3. What this means is that the Zone will change depending on direction of travel. Travelling between these stations and central London will actually be cheaper.
Fare zone 3 is an inner zone of Transport for London's zonal fare system used for calculating the price of tickets for travel on the London Underground, London Overground, Docklands Light Railway and, since 2007, on National Rail services.
Tourists normally use zone 1 where most of the tourist attractions are located, along with a lot of the popular hotel districts. Some of London's trendy neighbourhoods like Camden and Notting Hill are located in Zone 2.
Stratford International is a National Rail station in Stratford and a separate Docklands Light Railway (DLR) station nearby, located in East Village in London. Despite its name, no international services stop at the station; plans for it to be served by Eurostar trains never came to fruition.
Within London, all London Underground, National Rail, London Overground, TfL Rail and Docklands Light Railway stations are assigned to six fare zones. Fare zone 1 covers the central area and fare zones 2, 3, 4, 5 and 6 form concentric rings around it.
A Travelcard gives you unlimited travel within London zones 1-4 or 1-6 on the Underground, Overground, TfL Rail, Docklands Light Railway, buses, trams, and most National Rail services in London*.