On 19/06/2012 15:47, Paul Corfield wrote:

On Tue, 19 Jun 2012 15:11:56 +0100, Clive
wrote:

I may be going from central London to Amersham at the weekend - if so
will already have a travelcard which covers zones 1-6. I realise
Amersham is in Zone 9 and don't want to be clobbered with a penalty fare
on arrival. I would be happy to pay the excess from zones 6 to 9 by
Oyster Card, but I don't see how to do it. The train is hardly likely
to stop at a station in the boundary area long enough to allow me to hop
off, find an Oyster Validator, and hop on again, but with only about one
train every 30 mins, waiting for the next one isn't attractive.

I can't find anything about this on the TfL website, but it must be a
non-uncommon problem. Does anyone know how to solve it?

Is your Travelcard is on magnetic ticket stock rather than on an
Oyster card?

If it is magnetic then you will need to pay a cash excess at a ticket
office before starting your journey.

It's also now possible to buy extension tickets from Tube ticket
machines (an possibility which is fairly new I think) - "Extension
tickets" is an option on the main menu screen.