⚡ How Much Does Your AC Cost to Run per Month?
Calculate how much electricity your AC uses per day, month, and 3-month season — and how much that costs on your local tariff. Compare Inverter vs Non-Inverter, in USD, INR, AED, SAR, EUR, GBP or AUD.
📏1. AC Sizing & Technology
⏱️2. Usage & Cooling Load
💡3. Electricity Tariff & Currency
How Much Does Air Conditioning Cost to Run in the UK?
Air conditioning used to be rare in British homes — but after successive 35°C+ heatwaves, portable units and ductless splits are selling out every summer. The key question is running cost. Under the Ofgem energy price cap, the typical UK electricity unit rate in 2026 is around 24p per kWh (with a standing charge of roughly 50–60p per day on top). The calculator above is pre-set to 24p/kWh in GBP — check your bill or your supplier’s app (Octopus, British Gas, EDF, OVO, E.ON Next) for your exact unit rate and enter it for a precise answer.
Air Con Running Cost per Hour — Quick UK Reference
| Unit Type | Typical Power Draw | Cost per Hour @ 24p/kWh |
|---|---|---|
| Small portable AC (7,000 BTU) | ~0.8 kW | ~19p / hour |
| Large portable AC (12,000 BTU) | ~1.3 kW | ~31p / hour |
| Ductless split, one room (2.5 kW cooling, inverter) | 0.6–0.9 kW average | ~14–22p / hour |
| Multi-split, 3 rooms | 1.5–2.5 kW average | ~36–60p / hour |
A portable unit run 6 hours a day through a four-week hot spell costs roughly £32–£52 for the month — noticeable, but far less than most people guess. Use the calculator above with your own hours and tariff for daily, monthly, and seasonal totals.
Portable vs Split: The Efficiency Gap British Buyers Miss
Single-hose portable air conditioners are the least efficient cooling you can buy — they blow conditioned indoor air out of the window through the exhaust hose, pulling warm outside air back in through gaps. A properly installed inverter split system delivers the same cooling for roughly half the electricity:
- Portables typically achieve an EER of ~2.6; modern splits reach a SEER of 6–8 (A+++ label).
- At 24p/kWh, that difference is worth £15–£30 per month of regular use.
- Splits also work in reverse as air-source heat pumps — heating your room in winter for about a third of the cost of plug-in electric heaters.
If you’re on a smart tariff such as Octopus Agile, unit prices change every half hour — cooling in the early afternoon (often the cheapest window on sunny days thanks to solar generation) can cut costs by a third versus the 4–7pm peak.
Keeping British Cooling Bills Down
- Close blinds and curtains on south- and west-facing windows before midday — UK homes are built to hold heat, and preventing gain beats removing it.
- Seal the portable AC’s window kit properly; an unsealed hose panel can halve effective cooling.
- Set 24–25°C rather than 20°C — each degree lower adds roughly 6–8% to consumption, and 24°C already feels dramatically better than a 32°C heatwave.
- Run the unit’s dehumidify mode on muggy (but not scorching) days — drier air at 26°C often feels better than cold clammy air, for a fraction of the kWh.
Frequently Asked Questions — UK
How much does air conditioning cost per hour UK? Between 14p and 35p per hour for typical single-room units at the current price cap — see the table above, or use the calculator with your exact tariff.
Is air conditioning expensive to run in the UK? Less than most expect: even daily use through a hot month typically adds £30–£60 to the bill — comparable to a tumble dryer habit.
Do I need planning permission for a split air con unit? Usually not for a single small outdoor unit under permitted development, but flats, conservation areas, and listed buildings have restrictions — check with your council.