We investigated the variation in standby power consumption in 10 California homes. Total standby power in the homes ranged from 14 to 169 W, with an average of 67 W. This corresponded to 5–26% of the homes’ annual electricity use. The appliances with the largest standby losses were televisions, set-top boxes and printers. A short-term measurement of a home’s utility meter can provide surprisingly good estimates of total standby power if certain precautions are taken. The large variation in the standby power of appliances providing the same service demonstrates that manufacturers are able to reduce standby losses without degrading performance. Replacing existing units with appliances using 1 W or less of standby power would reduce standby power use by 68%, achieving a 7% reduction in annual electricity consumption. At least 70% of new appliance purchases in these homes will have standby power consumption.