Oyster card
Under 11s can travel free on London buses and trams at any time unaccompanied by an adult; they do not need an Oyster card or a ticket. Children aged 11 to 15 travel free on buses with an 11–15 Oyster photocard; without an Oyster card or Travelcard, they have to pay the full adult fare. Visitors can have a special discount added to an ordinary Oyster card at TfL's Travel Information Centres. There are also concessions for London residents aged 16 to 18.