competition text with a contract

[mollykins]

Not that i would want to text in for a tv show but . . .

on many tv shows now you get competitions or votes for who you want to win ect. and they say stuff like £1 plus the cost of one standard text.

But if you're on a contract mine's something like £5 a month for 100 calls and 100 texts (its more to start but if you remember and send away your reciept you get most of your money back so it works out at about £5 and they make their money through people losing the receipts/forgetting to send them away at the right time), do you get 1 message taken away plus another pound on your bill or do they take away 1 message plus another pounds worth of messages?