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Economy 7 calculator
Economy 7 gives you seven hours of cheaper electricity at night, but a higher day rate. Find out whether it saves you money based on how much you use overnight.
Defaults from our sources, last updated 2026-10-23.
Estimates only, not financial advice. Results use average UK figures and the assumptions shown. Your real costs depend on your home, tariff, region and installer quotes. Always get several quotes from certified installers and check current tariff rates before deciding. Don't rely on these results alone: see our disclaimer.
How to use it
Find your day and night rates on your bill or supplier app, and your yearly use on your annual statement. If your meter shows two readings, your night share is the night reading divided by the total. Defaults are illustrative Economy 7 rates of 32.0p (day) and 15.0p (night), compared with the 1 October to 31 December 2026 price cap average of 26.32p and 54.83p per day. Economy 7 rates vary much more by supplier and region than single-rate tariffs, so use your own figures where you can.
The break-even rule
Economy 7 saves money when your night share is above (day rate − single rate) ÷ (day rate − night rate), assuming the same standing charge. With the defaults that's (32.0 − 26.32) ÷ (32.0 − 15.0) = 33%. Use more than about a third of your electricity at night and Economy 7 wins. Use less and it costs you more.
| Night share | Economy 7 / year | Single rate / year | Economy 7 difference |
|---|---|---|---|
| 20% | £1,173 | £1,095 | +£78 |
| 30% | £1,115 | £1,095 | +£20 |
| 40% | £1,057 | £1,095 | −£38 |
| 50% | £999 | £1,095 | −£96 |
| 60% | £941 | £1,095 | −£154 |
3,400 kWh a year, which is Ofgem's typical Economy 7 consumption. Includes standing charges. "+" means Economy 7 costs more.
As a check, Ofgem puts the typical Economy 7 bill under the 1 October to 31 December 2026 cap at £1,046 a year for 3,400 kWh. With a 42% night share, our default rates give £1,045.
Who benefits from Economy 7?
- Storage heaters and hot water cylinders that charge overnight. These are the homes Economy 7 was designed for, and night shares of 50–70% are common.
- Electric car owners who charge overnight, although a dedicated EV tariff is usually much cheaper. Compare them in our smart tariff comparison.
- Not most homes with gas heating. Without big night-time loads, typical night shares are 20–30%, below break-even.
Tips if you're on Economy 7
- Check your off-peak hours. They're often not midnight to 7am, may shift by an hour with British Summer Time, and differ by region and meter.
- Run dishwashers, washing machines and tumble dryers on a timer overnight. See what each costs in our appliance running cost calculator.
- Avoid using storage heater boost or direct electric heaters in the day at the higher rate. Our electric heater running cost calculator shows how quickly it adds up.
FAQs
Is Economy 7 worth it?
Only if you use a large share of your electricity at night. With typical rates the break-even is about 33% of use at night. Homes with storage heaters or overnight EV charging usually pass it, while most other homes don't.
What times is Economy 7?
Seven hours overnight, but the exact times depend on your meter and region. They are often around 10pm–8am, set by your supplier, and can move by an hour in summer. Check your bill or ask your supplier.
Is Economy 7 covered by the price cap?
Yes. Ofgem caps Economy 7 too, with a typical bill of about £1,046 a year for 3,400 kWh in 1 October to 31 December 2026. Individual day and night rates vary by supplier.
Can I switch off Economy 7?
Usually, yes. Ask your supplier to move you to a single-rate tariff. With a smart meter this can often be done remotely. Older meters may need an engineer visit.
Related calculators
Sources
- Ofgem – Energy price cap unit rates and standing charges (1 Oct–31 Dec 2026)
- Ofgem – Summary of changes to the energy price cap, 1 October to 31 December 2026
- Ofgem – Changes to the energy price cap, 1 October to 31 December 2026
- Ofgem – Typical domestic consumption values (2026)
Estimates only, not financial advice. Results use average UK figures and the assumptions shown. Your real costs depend on your home, tariff, region and installer quotes. Always get several quotes from certified installers and check current tariff rates before deciding. Don't rely on these results alone: see our disclaimer.