Pay as you go
You can add money to an Oyster card or use contactless (card or device) straight away.
You only pay for the journeys you make and it's cheaper than buying a paper single or return ticket (train companies may offer special deals on some journeys).
In Zones 1-9, your fare is capped so you can travel as much as you like in one day or week (Monday to Sunday), without paying more.
Only contactless can be used to pay as you go on Elizabeth line services between Reading and Iver. Oyster cards are not accepted.