[From TfL, only a mere 12 days after the launch of Pre-Pay:]

Dear Mr X,

Welcome to Oyster Pre Pay.

On 4 January Oyster Pre Pay was introduced. This is a 'Pay As You Go'
facility for use on Tube and DLR services. Just charge money on to
your Oyster card and go! The fare for each trip is calculated based
on touching in the Oyster card at the start of the journey and
touching out at the end. Pre Pay fares are at a discount to the
normal adult single fares.

Did you know that all Oyster cards loaded with Travelcard season
tickets can also be loaded Pre Pay?

This means that when you travel beyond your Travelcard zonal validity
on tube and DLR, you no longer need to buy a ticket extension. Simply
charge your card with Pre Pay, and the system will ensure you pay the
correct extension fare for your trip. Just remember to always touch
your Oyster card flat on the yellow reader at the start and end of
your journey to ensure you pay the right fare. No more buying ticket
extensions and cheaper fares too!

As with Travelcard season tickets, you can top up Oyster Pre Pay
online or by phone, at Tube station touchscreen ticket machines or
ticket offices and selected National Rail stations and Ticket Stops
(newsagents). If your Oyster Pre Pay balance is reduced to less than
zero then you will need to load value on to your Oyster card before
you can use it again.

Please note that, as you cannot use Pre Pay for travel on most
National Rail services, you will still need to buy a paper ticket
extension before you travel out of zone on National Rail. NR services
where Pre Pay can be used are listed in the 'Fares and Tickets'
leaflet, which is available at all Tube stations.

For further information about Pre Pay or Oyster cards generally,
please visit http://www.oystercard.com

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services from us, please reply to this message with 'Unsubscribe' in
the subject line.

Yours sincerely

Chris Townsend
Director of Marketing, TfL