In message
, at
01:37:28 on Sun, 29 May 2011, Mizter T remarked:
Is there an easy way to do this? I can't find anything on line to help to
work out what the balance would be from, say, boundary zone 3 into zone 4.
Unless I'm missing something which is quite feasible at my time of life.

I assume you're referring to Oyster PAYG, what with your reference to
a 'balance'.

From the boundary of zone 3 (i.e. its outer edge) into zone 4, that
would just be a single fare for zone 4.

If the OP meant a station which was on the boundary of Z3/4, wouldn't he
have said that? Rather than using "BZ3" which you later agree is a NR
ticket only.
--
Roland Perry