Waiting lists are central to the allocation of medical care in the British National Health Service. But there have been few attempts to cost these lists. This paper argues that these lists have a cost to consumers. This cost cannot be estimated from the observed actions of demanders of care. A method of contingent valuation is proposed and used as a means of obtaining data to derive an estimate of this cost. The paper presents the methodology and derives a set of estimates of the disutility of time spent on a waiting list for nonurgent treatment.