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Under a see: Conditional fee arrangement, the proportion by which a lawyer's costs are increased to allow for the 'success fee'. The basic principle is that uplift should increase as the risk of losing the case increases. Currently uplift is limited by statute to 100%, and should be levied if the probability of losing the case is estimated to be better than evens (i.e., over 50%). Uplift should then decrease linearly to zero when the risk of losing is negligible.

Under the Contingency Fees Agreement Regulations (2000) the uplift is recoverable from the losing party provided that various formalities have been complied with.