Economy 7 explained: times, storage heaters and whether it’s worth it this winter

Written by: EnergySwitch editorial team · Last reviewed: 9 October 2026

Direct answer: Economy 7 is an electricity tariff with two unit rates. A cheaper off-peak rate applies for seven hours at night, and a higher peak rate applies for the other 17 hours. The off-peak hours are often midnight to 7am in winter and 1am to 8am in summer, but they depend on your supplier, meter and area. Check your bill or ask your supplier. The Centre for Sustainable Energy (CSE) says Economy 7 is usually cost-effective if you heat your home and water with electricity and use more than 40% of your electricity at night. That typically means storage heaters and a hot water tank timed to off-peak. If most of your use is during the day, a single-rate tariff is often better.

This guide explains how Economy 7 works, how to find your off-peak times, how to read a two-rate meter, how to get the most from storage heaters this winter, and how to compare Economy 7 tariffs properly.

What is Economy 7?

Economy 7 (E7) is a time-of-use electricity tariff. You pay different prices depending on when you use power:

• Off-peak (night) rate: applies for 7 hours, usually overnight. The CSE says it’s typically around a third of the peak price, though the gap varies between tariffs.
• Peak (day) rate: applies for the other 17 hours, and is higher than a typical single-rate tariff.

You need a meter that records day and night use separately. E7 only covers electricity. Gas, if you have it, is billed as normal.

E7 customers on a default tariff are protected by the Ofgem price cap, just like single-rate customers. For 1 October to 31 December 2026, Ofgem’s illustrative typical level for Economy 7 is about £1,046 a year. That’s a typical-usage figure, not your bill. Regional E7 rates are on our energy price cap hub. From 1 October 2026 to 31 March 2027, domestic electricity in Great Britain, including E7, carries 0% VAT. See VAT off electricity.

There are other time-of-use tariffs too. Economy 10, for example, gives ten cheaper hours, often split across the day. Check the exact times before you choose one.

Economy 7 times: when is the cheap rate?

Citizens Advice says the exact off-peak times depend on your supplier, your tariff and where you live, and may change when the clocks change. A common pattern is:

Some tariffs use different windows. To check yours:

1. Look at your bill. It should show two electricity unit rates and two sets of readings. Some bills also show the off-peak times.
2. Ask your supplier. It can confirm your exact hours.
3. Watch the meter. On a two-rate meter, note which register goes up late at night.

Radio teleswitch (RTS) meters: some E7 homes have a meter that switches rates using a radio signal. Ofgem says support for RTS meters has ended, and these meters may not work as expected. Citizens Advice warns that heating and hot water could stop working properly. If you still have one, contact your supplier about a smart meter replacement.

How to read an Economy 7 meter

An E7 meter has two registers:

• Two displays or rows of dials, often labelled “low” or “night” (off-peak) and “normal” or “day” (peak).
• One display with a button that cycles between the two readings.
• A smart meter set up for two rates, which sends readings automatically.

When you send readings, give both numbers and make sure each goes in the right box. If they’re swapped, your bill will charge night use at the day rate, or the other way round.

Storage heaters and Economy 7 in winter

Storage heaters are built for E7. They charge up with heat overnight at the off-peak rate and release it during the day. Citizens Advice gives practical advice on the controls.

Manual heaters with two dials

• Input (or “overnight charge”) sets how much heat is stored overnight. Citizens Advice suggests 5 or 6 in winter and 1 to 3 in spring and autumn. Set it before bed, and check the next day’s weather.
• Output (or “room temperature”) controls how fast the heat comes out. Turn it to the lowest setting overnight. Keep it low in the morning and afternoon so heat is left for the evening.
• If you keep running out of heat, raise the input rather than using boost.

The boost trap

Many heaters have a boost setting or switch, and some switch it on automatically when stored heat runs out. Boost uses peak-rate electricity. Citizens Advice warns that bills can be high if you use extra heat regularly. Turn off any “auto boost” setting if you can.

Modern heaters with digital controls

These can learn how much heat to store from the weather and your routine. Set the room temperature and timer. Citizens Advice says 18°C to 21°C is usually comfortable, and not below 21°C if the cold could make a health condition worse.

Hot water on Economy 7

Most E7 homes have a cylinder with two immersion heaters. The bottom element should run on the off-peak timer. The top “boost” element uses peak power. Citizens Advice suggests timing the main heater to finish an hour or two before off-peak ends, and avoiding boost. Check that the timer clock is set correctly, especially after the clocks change.

Safety: don’t cover storage heaters or hang washing on them. Citizens Advice suggests leaving about 30cm in front. The CSE advises not running washing machines or dishwashers overnight while you’re asleep, because of fire risk.

Is Economy 7 worth it? The 40% rule of thumb

The CSE’s rule of thumb: E7 is likely to be worth it if you use more than 40% of your electricity at night. This is usually because you have storage heaters and an electrically heated hot water tank.

To check your own case:

1. Find your split. Add up your night and day kWh from recent bills or your smart meter data. Your night share is night kWh ÷ total kWh.
2. Get the rates. Note the E7 day rate (D), the E7 night rate (N) and a comparable single-rate tariff (S), all in p/kWh.
3. Work out the break-even night share: (D − S) ÷ (D − N). If your actual night share is above this figure, E7 is cheaper on unit costs. If it’s below, single-rate is cheaper.
4. Add standing charges. Compare the daily standing charges too, then work out an annual cost for each tariff using your own kWh.

E7 tends to suit:

• homes with storage heaters and an off-peak hot water cylinder
• people who can genuinely move big loads, such as some EV charging, into the off-peak window

It tends to not suit:

• homes heated by gas, where electricity use is mostly daytime
• heat pump homes without heat storage. The CSE says E7 probably isn’t cost-effective there, but your supplier can confirm.

Switching off E7? The CSE warns that if you move to a single-rate tariff, an electrician should check the wiring. An old off-peak circuit could stay active and cause problems.

Economy 7 and smart meters

Ofgem says a smart meter gives you access to more flexible tariffs, including dual-rate tariffs. A smart meter can run Economy 7 or other time-of-use tariffs and send both readings automatically. That makes billing more accurate and shows you your real night share. If your E7 meter is old, or is an RTS meter, ask your supplier about a smart meter installation. Ofgem says installation is free.

How to compare Economy 7 tariffs

We don’t publish a “cheapest Economy 7 supplier” table. The right tariff depends on your day/night split, your region and the live rates. Instead:

• Compare using both your day and night kWh, not your total alone.
• Check the off-peak hours on each tariff, and whether your heaters can charge in that window.
• Include standing charges and any exit fees.
• Compare against a single-rate tariff as well, using the break-even calculation above.

Run a comparison with your meter type and usage on compare gas and electricity. Then see how to switch energy supplier. If you’re weighing up a fix, our winter 2026 fix guide explains the decision. The January to March 2027 price cap won’t be announced until 25 November 2026. Our January 2027 forecast explains why forecasts aren’t official figures. For more ways to cut use, see energy saving advice.

Ofgem review of the Economy 7 price cap: On 12 October 2026 Ofgem opened a call for input on how the price cap is set for Economy 7 and other time-of-use tariffs. It sets out three options, but nothing has been decided, and responses close on 20 November 2026. Read our explainer: Ofgem’s Economy 7 and time-of-use price cap review explained.

Economy 7 FAQs

What are the Economy 7 hours?

Seven off-peak hours, often midnight to 7am in winter and 1am to 8am in summer. The exact times depend on your supplier, tariff, meter and area, so check your bill or ask your supplier.

Is Economy 7 worth it?

The Centre for Sustainable Energy says it’s usually worth it if you heat your home and water with electricity and use more than 40% of your electricity at night. If you use most of your electricity during the day, a single-rate tariff is often cheaper.

How do I know if I’m on Economy 7?

Your electricity bill will show two unit rates (day/night or peak/off-peak) and two sets of meter readings. Your meter will have two registers, or one display with a button. If you’re unsure, ask your supplier.

Why do my storage heaters run out of heat by the evening?

The input may be set too low, or the output too high during the day. Citizens Advice suggests a higher input overnight in winter and a low output in the morning and afternoon. Avoid boost, which uses peak-rate electricity.

Is Economy 7 covered by the energy price cap?

Yes. If you’re on a default (standard variable) E7 tariff, Ofgem’s cap limits both unit rates and the standing charge. Ofgem’s illustrative typical E7 level for October to December 2026 is about £1,046 a year. Your bill depends on your usage.

Can I have Economy 7 with a smart meter?

Yes. Ofgem says smart meters give access to dual-rate tariffs, and they send both readings automatically. If you have an old radio teleswitch meter, contact your supplier, because support for those meters has ended.

Sources

• Centre for Sustainable Energy: Economy 7 tariff (reviewed July 2026)
• Citizens Advice: Using storage heaters and immersion heaters
• Ofgem: Get help with your smart meter (dual-rate tariffs, RTS meters)
• Ofgem: Changes to energy price cap between 1 October and 31 December 2026 (E7 covered by the cap; announcement dates)
• GOV.UK: Temporary zero rate of VAT for domestic electricity in Great Britain

Last reviewed: 9 October 2026. Written for Great Britain households. EnergySwitch is not Ofgem Confidence Code accredited. Always check live tariffs and your own day/night usage before switching.