Running costs · October 2026 prices
How much does air conditioning cost to run?
Real hourly costs for cooling and heating at today's UK energy prices, compared with electric heaters, portable units and gas central heating.
The quick answer
From about 11p an hour for a bedroom
- CoolingA 2.5kW bedroom unit costs around 11p to 21p an hour, and less once the room is cool.
- SummerCooling a bedroom 4 hours a day for 60 days costs about £38 for the whole summer.
- HeatingAs a heat pump it makes heat for about 5.7p per kWh, less than gas at around 8.9p.
Per hour
Air conditioning running cost per hour
Typical electricity use while cooling, at the October to December 2026 price cap of 26.32p per kWh.
| Unit size | Electricity used | Cost per hour |
|---|---|---|
| 2.5kW (bedroom) | 0.4 to 0.8kW | 11p to 21p |
| 3.5kW (living room) | 0.6 to 1.1kW | 16p to 29p |
| 5.0kW (open plan) | 0.9 to 1.5kW | 24p to 39p |
| 7.0kW (large space) | 1.3 to 2.2kW | 34p to 58p |
Inverter systems use the most power while cooling a hot room down, then slow down to hold the temperature. Actual use depends on the room, the weather and your settings.
Heating
What it costs to heat with air conditioning
Every system we install is an air-to-air heat pump. It moves heat from the outside air into your room, giving out around 4.6 units of heat for every 1 unit of electricity over a season (its SCOP).
That makes heating a room with air conditioning cheaper than a plug-in heater and, at today's prices, often cheaper than gas. Heating one room through a winter (about 3,000kWh of heat) costs roughly £172 with air conditioning, £266 with gas or £790 with an electric heater.
Cost per kWh of heat
Electricity 26.32p and gas 7.97p per kWh, Ofgem price cap October to December 2026.
Compared
Air conditioning vs other ways to keep cool
Save money
How to cut your air conditioning running costs
Set it to 22 to 24°C
Each degree cooler adds to your bill. Most people are comfortable at 22 to 24°C.
Use the timer or app
Switch on 20 minutes before you need it rather than running it all day.
Clean the filters
Dusty filters make the system work harder. Rinse them every few weeks in summer.
Close doors and blinds
Keep the cool air in and the sun out, especially in south-facing rooms.
Get the right size
A correctly sized unit runs gently and efficiently. Oversized units waste energy.
Service it every year
An annual service keeps efficiency high and catches problems early.
FAQs
Running cost questions
Still unsure? Call us on 0330 043 7869, 7 days a week.
How much does air conditioning cost to run per hour in the UK?
A 2.5kW wall mounted system typically costs about 11p to 21p an hour to cool a bedroom at the October 2026 price cap of 26.32p per kWh. Once the room is cool it often costs less, because the inverter slows down.
Is air conditioning expensive to run?
No. Modern split systems are rated A++ or better and use far less electricity than most people expect. Running a bedroom unit for 4 hours a day through a 60-day summer costs around £38.
Is it cheaper to heat with air conditioning or gas?
At current prices, an air conditioner with a SCOP of 4.6 produces heat for about 5.7p per kWh, compared with about 8.9p for a 90% efficient gas boiler. So heating a room with air conditioning can cost less than gas.
Is it cheaper to leave air conditioning on all day?
Not usually. It's best to set a comfortable temperature and use the timer or app to switch on shortly before you need it. Inverter systems use little power once they reach the set temperature.
How much does a portable air conditioner cost to run?
A typical portable unit uses about 1 to 1.5kW, which is around 26p to 39p an hour. That's often double the cost of a fitted split system for the same room.
What temperature should I set my air conditioning to?
For cooling, 22 to 24°C is comfortable for most people. Each degree lower adds to the running cost. For heating, around 20 to 21°C works well.
Cooler summers, cheaper winters
Prefer to talk? Call 0330 043 7869, 7 days a week.