The belief most Economy 10 households have, and what's really going on
The instinct sounds reasonable: ten cheap hours a day must beat seven. So Economy 10 must save more than Economy 7. It rarely works out that way. Economy 10 is a multi-register electricity tariff: the meter records usage in a peak bucket and one or more off-peak buckets, each with its own unit rate. Suppliers set the peak rate high enough to pay for the off-peak discount, with a margin on top. The standing charge is the same either way.
Why "more cheap hours = more saving" isn't automatic
What matters is not the cheap hours on offer. It is the share of your use that actually lands inside them. A house that genuinely shifts 45 per cent of its annual kWh into the three windows can save real money. A house that shifts 20 per cent pays more than it would on the single-rate cap, often by £80 to £200 a year, because the peak rate sits above the cap's single rate.
Why three windows instead of one longer one
Splitting 10 hours into three blocks was a 1980s grid-management trick: it spread storage-heater demand across the day so the network was not overloaded by one synchronised overnight surge. It is not a feature designed for the customer. The afternoon and late-evening slots exist for the grid's convenience, not yours. The fit checker further down lets you test how much of your day really lines up with them.
Why generic Economy 10 advice misleads UK households
Most explainers stop at "use your washing machine in the cheap windows". That is a definition, not advice. It ignores three things that decide whether you actually save:
- Your peak rate sits above the single-rate cap, so every kWh used outside the windows costs more than on a normal tariff.
- The afternoon and evening windows fall when working households are out, then cooking dinner. The windows do not match modern routines.
- Suppliers rarely publish Economy 10 unit rates publicly. The figures online are often old, regional, or for closed legacy tariffs.
The headline pitch (more cheap hours) hides the trade-off (a higher peak rate on the bulk of your use). That trade-off is the whole point of any time-of-use tariff. Economy 10's version just suits very few people.
How Economy 10 pricing actually works
An Economy 10 bill has three moving parts: a daily standing charge, a peak unit rate, and one off-peak unit rate that covers all three windows together. The meter does the splitting automatically.
The three off-peak windows (and why timings differ by region)
A typical Economy 10 day looks something like this:
- Overnight: roughly five hours, between midnight and 06:00.
- Afternoon: roughly three hours, between 13:00 and 16:00.
- Late evening: roughly two hours, between 20:00 and 22:00.
Start times shift by region and supplier. Scotland and parts of the north of England traditionally run their slot 30 minutes later than the south. Times also slide by an hour at the clock change, because many older meters track Greenwich Mean Time year-round. Always check the windows on your most recent bill, not a generic table.
Those regional quirks are exactly why a storage heater or immersion controller cannot reliably be programmed by hand: the off-peak windows differ by supplier, by region and at the clock change. To automate the timing correctly, connected devices read the schedule from Selectra's Selectra's price planning API, which returns the exact priced periods for a given Economy 10 tariff instead of leaving the household to keep a timer in sync.
How Ofgem's cap applies to each register
Multi-register tariffs sit under the same Ofgem default tariff cap as single-rate ones, with a maximum unit rate for each register (peak and off-peak) and a maximum standing charge, set per region and republished every three months.
A deeper off-peak discount is usually paid for by a higher peak rate, because each region's multi-register cap lands at roughly the same blended cost as the single rate for an average user. You only beat the average if your use is above-average off-peak. Specific Economy 10 unit rates vary by region and supplier: check your latest bill rather than rely on a quoted figure. UNVERIFIED: confirm current regional cap-table figures before republishing.
Quick comparison at the Ofgem 3,900 kWh household
The table below shows how the same household would fare on three setups, using the Ofgem single-rate cap for the baseline and illustrative E7 and E10 split rates. Treat the E7 and E10 figures as worked examples, not quotations:
| Off-peak share of use | Single rate (cap) | Economy 7 (illustrative) | Economy 10 (illustrative) |
|---|---|---|---|
| 25% in off-peak | £1,171 | £1,234 | £1,254 |
| 40% in off-peak | £1,171 | £1,156 | £1,176 |
| 55% in off-peak | £1,171 | £1,078 | £1,098 |
Single-rate uses the Ofgem cap published for 1 April to 30 June 2026 (24.67 p/kWh, 57.21 p/day). E7 and E10 rows use illustrative peak/off-peak splits typical of legacy tariffs. Use the calculator below with your own bill numbers for an accurate read.
Where Economy 10 households quietly overpay
Two patterns show up on bills again and again, and both are about how people end up on the tariff in the first place.
Inheriting an E10 meter without the lifestyle to match
The most common case is a flat or terraced house bought or rented with an Economy 10 meter already installed, usually because a previous occupant had storage heating. The new household has gas central heating, no storage heaters, no afternoon laundry routine, and goes to bed before the late-evening window opens. They pay a peak rate above the single-rate cap on roughly 80 per cent of their use, for the privilege of cheap kilowatt-hours they never consume. Switching to single-rate typically gains £100 to £200 a year, often with no meter swap (most multi-register meters can be reprogrammed, or replaced with a smart meter free of charge).
Suppliers that won't switch you off E10 easily
A smaller but more frustrating pattern: some properties have an Economy 10 setup tied to a specific supplier, especially in housing association stock or older blocks of flats. The supplier may take weeks to authorise a tariff change, quote a fee for reprogramming the meter, or simply tell new customers that Economy 10 is the only tariff available at that address. None of this is allowed under Ofgem's switching rules. If you hit this wall, ask in writing which Ofgem licence condition prevents them from offering a single-rate tariff at your address. The answer is "none", and putting it in writing usually unsticks the process.
Insider truth: Economy 10 is a legacy product, not a market product
Suppliers do not advertise Economy 10. There is no "switch to Economy 10" page on a major brand's website. The tariff exists to honour the contracts of households whose property still has the right meter, and to keep storage-heater customers warm at a manageable price during the energy transition.
The Radio Teleswitch Service (RTS), the radio signal that flipped many older multi-register meters between peak and off-peak, was switched off on 30 June 2026. Ofgem's RTS programme required suppliers to migrate affected households to smart meters or move them off the legacy tariff. For what the switch-off means in practice, read our guide to checking whether your meter was affected.
New time-of-use tariffs in 2026 are smart-meter-based and designed around EV charging and heat pumps, not storage heaters. Economy 10 is not being expanded: it is being managed gently to an end.
Economy 10 fit checker
Set how much of your annual use lands in each of the three off-peak windows, plug in the rates from your bill (or keep the defaults), and the tool will show whether Economy 10 actually saves you money versus the single-rate cap, and at what off-peak share you would break even.
Your electricity use
Total off-peak share:
The three windows add up to more than 100%. Reduce one slider so the total stays at or below 100%.
Your rates (edit from your bill)
Defaults use the Ofgem single-rate cap for 1 April to 30 June 2026.
Result for your household
Annual cost on Economy 10
£
Annual cost on single-rate
£
Difference
£
Plain verdict: at your current settings.
Break-even off-peak share: . Below this share of your annual use in the off-peak windows, single-rate is cheaper. Above it, Economy 10 wins.
With these rates there is no realistic break-even point: single-rate is either always cheaper or always more expensive than this Economy 10 tariff.
What you should actually do
The decision splits cleanly in two. There is no third "stay where I am because switching is complicated" option: Economy 10 is being run down, and your supplier will make the call for you sooner or later.
Keep Economy 10 if your lifestyle genuinely fits
Keep it if you tick most of these:
- You have modern, well-insulated storage heaters that you top up in the afternoon window during cold spells.
- You are home during the day and run your washing machine, dishwasher or tumble dryer in the afternoon slot.
- The fit checker above shows an off-peak share above your break-even point, with margin.
- You have checked the windows on your bill match when you actually use the appliances.
If that is you, the tariff is doing its job. Make sure your meter is a smart multi-register one (post-RTS), and that your supplier sends a half-yearly readout broken down by register so you can verify the maths.
Switch to single-rate or a modern TOU/EV tariff if not
For everyone else, including most households who inherited the meter, ask your supplier for either a single-rate tariff or a modern time-of-use (TOU) smart tariff. TOU tariffs use your smart meter to apply a deeper overnight discount (often four to seven hours at a much lower unit rate than Economy 10's off-peak) and are designed around EV charging, heat pumps and batteries, not 1970s storage heaters.
There is no meter installation fee for moving from Economy 10 to single-rate in 2026 if you accept a smart meter, which most suppliers fit free of charge. That same meter can later host a TOU tariff if your lifestyle becomes more shiftable.
Take 30 seconds
Run your own numbers in the checker above before you ring your supplier. Note the break-even off-peak share. If your real off-peak use is below it, ask in writing to move to a single-rate tariff with a smart meter.
Selectra UK does not pay or receive commission for advice given in this guide.
Conclusion: a meter is a tool, it should match how you live, not the other way round
Economy 10 was designed when storage heating was the default for electric homes, and when households organised their day around the windows on the bill. That world is largely gone. For the small minority who still live that way, the tariff still works. For everyone else, the three cheap windows are paid for in a higher peak rate that quietly eats the saving.
The right question is not "should I switch off Economy 10?" but "does my lifestyle put more than the break-even share of my electricity into those three windows?". The widget above answers that in 30 seconds. If the answer is no, the meter is the wrong tool for your house, and your bill has been telling you so every quarter.
Frequently asked questions
What is Economy 10 in the UK?
Economy 10 is a multi-register electricity tariff that gives you 10 hours of cheaper, off-peak electricity each day, split across three separate windows: usually overnight, mid-afternoon (around 13:00 to 16:00) and late evening (around 20:00 to 22:00). The exact times depend on your supplier and region. The remaining 14 hours of the day are charged at a higher peak rate.
Is Economy 10 cheaper than a standard single-rate tariff?
Only if you can shift a large share of your electricity into the three off-peak windows. As a rough guide, you typically need at least 40 to 45 per cent of your annual use in off-peak hours to break even against the Ofgem price cap single rate. Below that, Economy 10 usually costs more, because the peak rate is higher than the standard single rate.
Which suppliers still offer Economy 10 in 2026?
Far fewer suppliers offer Economy 10 than Economy 7. Availability changes year to year and some suppliers only keep existing Economy 10 customers rather than signing up new ones. Some properties also come with a clause that forces you to stay with a specific supplier if you keep the Economy 10 setup. Always ring the supplier listed on your meter before assuming you can switch.
My RTS meter stopped working. What happened?
The Radio Teleswitch Service (RTS), which sent the signal that flipped many older Economy 7 and Economy 10 meters between rates, was switched off on 30 June 2026. Affected households have been moved to smart meters with an equivalent multi-register tariff, or asked to switch to a single-rate tariff. If your bill suddenly looks wrong, contact your supplier to confirm which tariff you are now on.
Is Economy 10 better than an EV tariff?
For most households with an electric car, no. Modern time-of-use EV tariffs offer a single deep overnight discount (often around five to seven cheap hours at a much lower rate than Economy 10 off-peak), with a peak rate that is usually no worse than the Ofgem cap. Economy 10 is designed for storage heating, not for charging a car, and the afternoon and evening windows rarely line up with how people charge.