A time of use tariff charges different electricity rates at different times, usually with higher peak prices and cheaper off-peak or shoulder periods. The times and rates vary between retailers and distribution networks, and you generally need a compatible smart meter. It may suit households that can shift usage, such as running the dishwasher, washing machine or electric vehicle during cheaper periods, but it could cost more if most of your electricity is used at peak times. Check the tariff details and compare your usage with other plans before switching.