Abstract In this article the economic consequences of nuclear accidents are expressed as a surcharge on the capital costs of each new station. An accident at any nuclear station may cause electric power utilities elsewhere to reduce output from the same type of reactor, as happened after Three Mile Island. The size of the accident surcharge therefore increases with the worldwide use of a reactor type. Plausible assumptions for the UK give a surcharge of 7.5% of total capital costs for the pressurized water reactor (PWR), compared to 2.5% for a lesser-used design such as the advanced gas-cooled reactor (AGR). These results are subject to considerable uncertainty but they clearly indicate that the accident surcharge could be of some importance in the choice of reactor for future power stations.