To provide a water heater capable of saving fuel consumption without giving any feeling of discomfort to a user.

In a water heater 1 for supplying hot water to a general hot water supply faucet 2 and a bath hot water supply faucet 3 to be used for bathing purpose, the control unit 9 of the water heater 1 estimates whether hot water to be supplied from the water heater 1 is used for a bathing purpose or other purpose than the bathing purpose. When it is assumed that the hot water is for bathing purpose, hot water is supplied with the set temperature of the hot water as the target temperature for the hot water supply. Alternatively, when it is assumed that hot water is used for other purpose than the bathing purpose, hot water is supplied with the energy-saving hot water supply temperature to be set lower than the hot water supply set temperature as the target temperature for the hot water supply, and the fuel consumption is suppressed when supplying hot water for the purpose other than the bathing purpose.