When Should You Turn the Heating On in 2026? What October’s Price Cap Rise Means for Your Home

# When Should You Turn the Heating On in 2026? What October's Price Cap Rise Means for Your Home

By Bradley’s Radiators · September 2026 · 6 minute read

It happens every September. The first properly cold evening arrives, someone reaches for the thermostat, and someone else says "not yet — it's only September." The great British switch-on debate is back.

This year, though, the timing question comes with a twist. On 1 October 2026, Ofgem's energy price cap rises to £1,723 a year for a typical household — an increase of around 4%, or roughly £60. So when you switch on, and what you switch on, matters a little more than usual.

Here's the honest, practical answer — plus a ten-minute radiator check that will save you money all winter.

The short answer

Most heating professionals work to a simple rule of thumb: once the outside temperature sits consistently below about 15°C, it's time. Below that point, most homes lose heat faster than everyday activity puts it back, and rooms start to feel genuinely cold rather than just fresh.

In a typical year, that moment arrives somewhere between mid-September and early October for most of the UK — earlier in Scotland and the North, later in the South East. There's no prize for holding out until November. Cold homes are harder (and more expensive) to reheat, and damp and condensation problems start long before you feel uncomfortable.

The better question isn't "what date?" — it's "is my home ready to heat efficiently the moment I switch on?" More on that below.

What's changing on 1 October 2026

Three things worth knowing before the boiler fires up:

The price cap rises to £1,723. From 1 October to 31 December 2026, the cap for a typical dual-fuel household paying by Direct Debit goes up by around 4% — about £60 a year, or £5 a month. If you're on a standard variable tariff (most households are), your unit rates will rise. You can see the full unit rates on Ofgem's price cap page.

VAT comes off electricity — but not gas. From 1 October 2026 to 31 March 2027, the 5% VAT on electricity is cut to 0%. Gas keeps its 5% VAT. For the vast majority of UK homes with gas central heating and wet radiators, the VAT cut softens the blow slightly on the electricity side, but your heating cost still rises with the cap.

January is forecast to rise again. Cornwall Insight currently forecasts a further rise of about 9%, to around £1,872 a year, when the cap resets on 1 January 2027. In other words: the cheapest unit of energy this winter is the one you don't waste.

What temperature should you set?

The Energy Saving Trust recommends setting your thermostat between 18°C and 21°C — warm enough for health and comfort, without paying to heat air you don't need. The UK average sits just under 21°C, and turning down by a single degree is widely estimated to trim around 10% off your heating bill. Most people can't feel one degree. Everyone can feel £100.

Two more habits that cost nothing:

• Time it, don't leave it. Set the heating to come on around half an hour before you get up, and off half an hour before bed. (If you have a heat pump rather than a boiler, the advice differs — heat pumps run most efficiently at a low, steady output all day.)
• Heat the rooms you live in. Thermostatic radiator valves (TRVs) let you run bedrooms and spare rooms cooler than the living space. Just don't turn off the radiator in the room where your main thermostat lives, or it will keep calling for heat.

The ten-minute radiator MOT (do this before you switch on)

Radiators that sat cold all summer rarely come back at full strength. Before the first proper cold snap, walk the house and check each one:

1. Bleed anything that gurgles. Air rises to the top of the system over summer. If a radiator is cold at the top and warm at the bottom, bleed it with a radiator key until water spits through, then check your boiler pressure afterwards (top up to around 1–1.5 bar if it's dropped).

2. Feel for cold patches at the bottom. Cold at the bottom but warm at the top usually means sludge — rusty deposits that block flow and can cut a radiator's heat output dramatically. One sludged radiator is a job for a flush; several is a conversation with your heating engineer about a system clean and inhibitor.

3. Check the balance. If the radiators nearest the boiler roar while the furthest bedroom barely warms, the system needs balancing — adjusting the lockshield valves so every room heats evenly. It's a fiddly but free fix.

4. Set every valve deliberately. TRVs at 5 in empty rooms are money out of the window. Living spaces at 3–4, bedrooms at 2–3, spare rooms at 1–2 is a sensible starting point.

5. Uncover them. A sofa pushed against a radiator, or full-length curtains draped over one, can swallow a large share of its heat. Radiators need clear air in front of them to convect properly — that's the whole job.

When holding out costs more than switching on

Here's the part most "money-saving" articles skip: no thermostat trick can fix a radiator that's wrong for the room.

If a room never quite gets warm, the usual culprit isn't the boiler — it's an old, tired or undersized radiator running the boiler longer and harder for less heat. Every radiator has a rated heat output (measured in BTUs or watts), and it needs to match the room's size, windows and outside walls. Get that right and the room reaches temperature quickly and holds it; get it wrong and you're paying October 2026 prices for lukewarm.

A few honest pointers if you're weighing up a replacement this autumn:

• Size for the room, not the wall gap. Work out the heat requirement first, then choose the style. Our team can calculate the BTU requirement for any room, so just ask.
• Short on wall space? Go vertical. A tall, narrow radiator delivers full output from a slice of wall a sofa or sideboard can't use anyway.
• Period home? Column radiators remain the gold standard — the traditional cast-iron look with modern steel efficiency, and deeper 3, 4 and 6 column versions produce serious output for larger or draughtier rooms.
• Make it a feature, not an apology. Radiators no longer have to be white boxes. An anthracite grey or jet black column radiator anchors a neutral scheme, and our RAL colour range runs all the way to flame red and mint green if the room deserves a statement.

Replacing a radiator sounds disruptive; in practice a straightforward swap is usually done within a morning, and autumn — before engineers hit peak winter breakdown season — is the smart time to book it.

Frequently asked questions

Is it cheaper to leave the heating on low all day?

For homes with a gas boiler, no — the Energy Saving Trust's advice is to heat your home only when you need it, using a timer. Leaving it on constantly means paying for heat while the house is empty or asleep. The exception is heat pumps, which are designed to run low and steady.

What date does the average UK household turn the heating on?

Analysis of Met Office temperature data typically puts the national switch-on point between mid-September and early October — the point when daily temperatures settle below about 15°C. Colder years pull it into the first week of September.

Does bleeding radiators actually save money?

Yes. Trapped air means part of each radiator produces no heat, so the boiler runs longer to hit the same room temperature. Bleeding takes two minutes per radiator and costs nothing.

When does the energy price cap change next?

The £1,723 cap runs from 1 October to 31 December 2026. Ofgem resets the cap quarterly, so the next change lands on 1 January 2027 — and current forecasts expect a further rise.

Ready for winter?

Whether you need one radiator that finally matches the room or a whole-house refresh, Bradley’s Radiators delivers premium designer radiators to mainland England and Wales — with professional installation available in our local area (pop your postcode into our checker to see if we cover you).

Browse column radiators, explore our coloured radiator range, or get in touch for a free BTU calculation for any room.