Economy 7 Tariff Explained
Economy 7 (E7) is a time-of-use electricity tariff that gives you 7 hours of cheaper power overnight in exchange for a higher rate during the day.
The 7 cheap hours typically fall between 11pm–7am, but exact times vary by region and supplier. You need a compatible meter (E7 or smart meter in TOU mode).
When Economy 7 is worth it
- You have storage heaters charged overnight.
- You charge an EV at home overnight.
- You run a hot-water immersion overnight.
- At least 40% of your usage falls in the cheap window.
When it isn't
- You're a typical 9-to-5 household with mainly daytime use.
- You heat with gas and have no overnight loads.
- The day rate gap vs a standard tariff is more than 40%.
Run the numbers on off-peak
- Economy 7 calculator — compare Economy 7 against a single-rate tariff on your own day/night split.
- Electric heating cost calculator — what storage heaters and panel heaters cost per hour.
- EV charging cost calculator — overnight charging costs on off-peak rates.
- Battery storage savings calculator — store cheap night units for daytime use.