Economy 7

Houses using the Economy 7 tariff require a special electricity meter which provides two different readings - one for electricity used during the day, priced higher, and the other for the night, priced lower. The night (off-peak) period lasts for a total of seven hours, hence the name; however it may not be a continuous period, as it may alternate between the two prices during the night.

The term was coined by Jon Marshall. The first mention of Economy 7 is in 1978:

A new off-peak tariff known as the 'Economy 7' tariff was introduced in October [1978]. It featured a seven-hour night rate some 20 per cent cheaper than most night-time tariffs, made possible by economies in the night-time operation of the system.

In more recent years the difference between day and night rates has become smaller, with a reduction of about 33% (though dependent on the supplier). The Economy 7 tariff results in either or both of an increased standing (fixed) charge or increased daytime rate.

Timing and switchover

Appliances such as night storage heaters and hot water boilers are often on a separate circuit which is switched on only when the night rate is activated, however any electrical appliance on an ordinary circuit during this period also runs at the lower rate of billing. Some appliances such as dishwashers and washing machines include timers to allow them to be set to run during times when the night rate is active, but are connected to a normal circuit.

In newer houses, a digital meter automatically switches to record both ranges.

The specific times when Economy 7 applies vary between different regions, seasons, and sometimes individual meters. For example, the seven-hour period might start at 1:30 am during British Summer Time or 12:30 am during Greenwich Mean Time (winter). Some regions use radio teleswitching to control consumers' systems and vary the timing. This uses data superimposed on the 198 kHz long wave signal that was also used by BBC Radio 4, however this service was discontinued just after 12:00 BST on 30 June 2026, when the 198 kHz network from all three of its source transmitters, that being Droitwich in Worcestershire, England, as well as Westerglen and Burghead in Scotland, was officially shut down permanently.