How much does it cost to run an electric oven per hour in the UK?
A mid range electric oven uses about 0.87 kilowatt hours for a standard cycle, which is 22.7p at the Ofgem cap rate of 26.11p per kWh. A full hour of baking from cold, counting the preheat, works out at around 1.15 kilowatt hours or 30p, and every hour after that adds about 22p because the cavity is already hot.
Why ovens are not measured in watts
Every other appliance on this site has a wattage. An oven has a connection rating instead, and the two are not the same thing.
Bosch lists a connection rating of 2,400 watts for the HHF113BR0B, a 66 litre single oven in energy class A. That figure is what the element draws when it is actually on, and it is on continuously only during the preheat. Once the cavity reaches temperature, the thermostat cycles the element on and off, and the oven spends most of a long bake drawing nothing at all.
Manufacturers get round this by publishing energy per cycle on the label instead. Bosch quotes 0.79 kilowatt hours a cycle in fan forced mode and 0.98 in conventional mode for that oven, Neff quotes 0.81 and 1.04 for the B6ACH7HH0B, and a Bosch Series 8 comes in at 0.69 and 0.87. We use 0.87 kilowatt hours as the everyday figure for a mid range oven, with 0.69 at the efficient end and 1.04 at the top.
Work it out for your own electric oven
Type in the wattage from the plate on the back, then your own unit rate. The numbers update as you type.
What an hour costs, and why the second one is cheaper
The preheat is the expensive part. Bringing 66 litres of air and a heavy steel cavity up to 180 degrees takes about 12 minutes at the full 2.4 kilowatts, which is 0.48 kilowatt hours before any food goes in. After that the element cycles at roughly a third of its output to hold temperature, or about 0.84 kilowatt hours an hour.
| How long the oven is on | Energy used | Cost at the cap rate | US cost |
|---|---|---|---|
| Standard label cycle | 0.87 kWh | 22.7p | 16c |
| 30 minutes from cold | 0.73 kWh | 19.1p | 13c |
| 1 hour from cold | 1.15 kWh | 30.0p | 21c |
| 2 hours from cold | 1.99 kWh | 52.0p | 37c |
| 3 hours from cold | 2.83 kWh | 73.9p | 52c |
| Sunday roast, 3 hours, oven full | 2.83 kWh | 73.9p | 52c |
The last two rows are identical on purpose. An oven costs the same whether it holds one tray or four, which is the single most useful fact on this page and the reason batch cooking works.
| Appliance | Typical draw | Usage we assume | Per hour (UK) | Per usage (UK) | Per month (UK) | Per hour (US) |
|---|---|---|---|---|---|---|
| Electric oven | 0.87 kWh a cycle | per standard oven cycle (energy label) | 22.7p | 22.7p | £4.92 | 16.0 cents |
Rates: Ofgem cap 1 July to 30 September 2026 at 26.11p per kWh (source), EIA residential average June 2026 at 18.34 cents per kWh (source). Checked 2026-09-22.
The sum, if you want to check your own
Take the connection rating from the plate inside the door frame, divide by a thousand, and multiply by the preheat time in hours. Then add the running time multiplied by the same kilowatts multiplied by about 0.35 for the duty cycle.
For a 2.4 kilowatt oven baking for 90 minutes from cold, that is 2.4 multiplied by 0.2 hours of preheat, which is 0.48 kilowatt hours, plus 2.4 multiplied by 1.3 hours multiplied by 0.35, which is 1.09. The total is 1.57 kilowatt hours, or 41p at the current rate.
If your oven has an energy label, the per cycle figure on it is the more reliable starting point, because it was measured rather than estimated.
Six ways to bring the figure down
- Use the fan forced setting rather than conventional. Bosch and Neff both publish about a 20 per cent saving per cycle for the same oven, which is 5p on every meal for the price of turning a dial.
- Stop preheating for anything that cooks longer than 40 minutes. Casseroles, jacket potatoes and roasting vegetables do not care about the first ten minutes, and you save the whole 0.48 kilowatt hours.
- Fill the oven whenever it is on. A second tray of vegetables, a tray of flapjacks or tomorrow's potatoes cost nothing extra.
- Keep the door shut. Each opening drops the cavity temperature by 20 degrees or more, and the element has to make that back at full power.
- Check the door seal. A perished seal on an older oven leaks heat continuously and shows up as longer cooking times before it shows up as a bill.
- Turn the oven off ten minutes early for anything baked. The cavity holds enough heat to finish the job, which is free energy you have already paid for.
What an hour costs in the United States
At the EIA residential average of 18.34 cents per kilowatt hour, an hour from cold costs 21 cents and a three hour roast costs 52 cents. American ovens typically run on a 240 volt circuit with a higher connection rating than British ones, often 3 to 5 kilowatts, so the preheat is faster and the energy per cycle ends up broadly similar. In California at nearly 35 cents that hour becomes 40 cents, and in Texas at under 16 cents it is 18 cents.
Against the rest of the kitchen
Compare like for like, meaning the same food rather than the same hour. An air fryer at 1750 watts for 25 minutes costs 19p and feeds one or two. A halogen oven at 1300 watts for half an hour costs 17p. A slow cooker at 200 watts for eight hours costs 42p and produces a meal an oven could not match. A microwave reheating for five minutes costs 2p.
The oven only looks expensive when it is used for one small thing. Used properly, with the shelves full and the fan on, it is the cheapest way to cook for a family in the house.
Common questions
How much does it cost to run an oven for 2 hours?
About 52p at the current cap rate. The first hour carries the preheat and costs around 30p, and the second hour only has to hold temperature in a cavity that is already hot, so it adds roughly 22p. Three hours comes to about 74p on the same basis.
How much does it cost to run an oven at 180 degrees for an hour?
Around 30p from cold. A hotter setting costs a little more because the cavity loses heat faster to the kitchen, but the difference between 180 and 220 degrees over an hour is a few pence rather than a different order of cost.
Is it cheaper to use an air fryer than an electric oven?
For one or two portions, yes. A 1750 watt air fryer for 25 minutes uses 0.73 kilowatt hours and costs 19p, against 23p for an oven cycle. For a family meal the oven wins easily, because one cycle feeds four people and the air fryer needs three batches to do the same.
Is it cheaper to use a slow cooker than an electric oven?
Per hour the slow cooker is far cheaper at 200 watts, which is 5.2p, but it runs for eight hours and so a full batch costs about 42p against 30p for an hour in the oven. The saving comes from what you cook rather than from the appliance, since a slow cooker turns cheap cuts into a meal the oven would need three hours to manage.