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It is accepted by judges and academics alike that the restitutionary liability of an unjust payee ought to encompass both the principal sum transferred, and an additional sum that reflects its “use value” over the period between receipt and restitution. The issues that divide opinion concern the proper method of conceptualising and calculating use value. Two theories have predominated: the first is that the defendant should pay compound interest on the principal sum for the period of the enrichment, as complete restitution of an enrichment unjustly received; the second is that the defendant should pay simple interest on the principal sum for the period of the enrichment, at a rate that (broadly) reflects the claimant’s loss of use of that sum. In this article, I argue that there is a third, better, option: the defendant should be entitled to discharge her restitutionary duty by restoring the principal sum at any date before or in compliance with a court order to that effect. There should be no attendant liability for interest, compound or simple, as the “use value” of money paid.