On May 12, 9:47*am, "Ian F." wrote:
(Apologies in advance if this message doubles up - I have some issues with
my usual news server - news.individual.net)

I have a PAYG Oyster card. Today I have to get from Balham to Turnham Green
and was intending to take a Southern East CroydonMilton Keynes train that
goes direct from Balham to West Brompton. I'm intending to return by tube
without using an overground service.

Although PAYG Oyster cards are valid on Southern services via West Brompton,
I can't get through the barriers at Balham with my PAYG card so I assume
I'll have to buy a single ticket to cover me from Balham to WB and then use
my Oyster from WB to Turnham Green and for the rest of the day.

Unless, of course, you know differently...

Ian

Oyster PAYG is only valid on the Southern service between Clapham
Junction and Watford Junction (including all intermediary stations).
This TfL webpage states where Oyster PAYG can be used on National Rail
- see in particular the PDF map it links to.

In your case, if you want to use the Southern service from Balham to
West Brompton then you can either...

(a) Buy a single ticket for Balham to West Brompton - at WB when
changing to the District line, make sure you touch-in on one of the
standalone Oyster readers at the entrances to the District line so as
to start your Oyster PAYG journey.

(b) Buy a single ticket from Balham to Clapham Junction, then exit the
train at CJ and touch-in on one of the standalone Oyster readers on
platform 16 (which you will travel through) and then try and jump back
on the same train, which might just be do-able! Otherwise you could
walk over the overbridge to platform 2 (the other side of the station)
to catch the London Overground service to West Brompton which usually
departs a couple of minutes after the Southern service.

(c) Buy a Day Travelcard, if you're travelling off-peak (i.e. after
09:30). A zones 1-4 off-peak Day Travelcard costs £6.30. This is
definitely the option to go for if you're making any other journeys
apart from a Balham to Turnham Green round trip.