Good Lawyer Guide's response

. If the claim is less than £5,000 each party will usually pay its own costs whatever the outcome of the case. If it is over £5,000, normally the party who loses will be ordered to pay the other party’s costs. But if the judge thinks this is unfair, he or she can make a different order. For example, if your supplier wins the case but the judge takes the view that you caused unreasonable delay, or you turned down a perfectly reasonable offer to settle the case earlier in the proceedings, he can reduce the amount of costs awarded in your favour.

Also, the losing party is usually ordered to pay what is called ‘assessed costs’ so if you win, you may receive less than they have actually incurred in instructing solicitors.