Thank you for all your replies.
To save opening another thread.
Does anyone know how much TFL takes if you use contactless to authorise your card?
I don't have an oyster anymore and there is no need to get one as no railcard after 5th Feb. I'm travelling on the 6th Feb, and wanted to check whether I need to leave so much on my card to use it to start the charges, as I've read that they take £10 when my fares will be less than that.