The sun is beaming, and if you’ve been getting flashbacks of sweaty summers past, you may be thinking about how to keep your home cool this time around. But with the typical household energy bill expected to rise by £1,973 on average in July, it’s worth being aware of the cost of running an air conditioner.
Unlike other countries, such as the United States, UK households don’t usually have built-in AC units due to the traditionally mild climate. But according to Ben Gallizzi, energy expert at Uswitch, Brits are increasingly investing in keeping homes cool.
“About four million UK households have air conditioning, and the numbers are growing every year as summers get hotter,” he says. “Air con can make life more comfortable and potentially improve sleep quality during heatwaves.” But the running costs can add up. To get more insight, we consulted the experts.
Read more: Best portable air conditioners to keep your home cool
How much does it cost to run a portable air conditioner?
As a general rule of thumb, you can expect the cost of running your air conditioner to fall between 20p and 60p an hour, says Alex Peters, a cost expert at .
“The cost of running an air conditioning system can vary depending on a number of factors, including the type of system you have, its age and efficiency, how long you use it for, and how well insulated your property is,” he adds.
Gallizzi from Uswitch gave a similar running cost. “Portable air conditioning units typically use 1kW of power, which means they will currently cost you nearly 25p an hour in electricity.”
If you’re considering getting a built-in system, Gallizzi says these units “can be even more energy-intensive, with a 2.7kW unit costing you 67p an hour when it’s running at full power.”
How to keep costs down
While air conditioners aren’t generally cheap to run, there are ways that you can keep costs down.
“Making sure windows are properly sealed helps keep cool air in, while investing in a smart thermostat can improve how efficiently your system runs,” says Alex. “Regular maintenance is also key to ensuring your air conditioner continues to operate as efficiently as possible over time.”
You can maintain your air conditioning unit by cleaning the filters every month or two, checking the coils, and unclogging the drain.
Which air conditioner should I choose?
Choosing the right air conditioner will also make a noticeable difference in keeping costs down.
“Opting for an energy-efficient model and ensuring it’s correctly sized for the space will help keep long-term running costs down,” Alex explains.
“Portable monoblock units, for example, tend to have a lower upfront cost and can be moved between rooms, but they are generally less efficient and are often better suited to short-term or occasional use.
“In contrast, split systems are more efficient, quieter, and offer better temperature control, making them ideal for those looking for a cost-effective long-term solution to air cooling”.
Not looking to invest in an air conditioning unit? Ben has a short-term solution: “A desktop fan is far less energy-hungry – using about 1p an hour in electricity – and can be bought for as little as £10.”
Read more: Best fans for 2026, tested and reviewed
ElectriQ ecoplus 10000 BTU smart portable AC with heater
Our best portable air conditioner is the ElectriQ ecoplus 10000 BTU smart portable AC with heater. “This electriQ ecoplus model is one of the most versatile units I have used – and easily the best portable air conditioner”, said Joanne Lewsley model in her guide to the best portable air conditioners.
“It’s genuinely effective at cooling a room quickly and the swing panel allows the air to waft gently around, ensuring there are no icy spots, just ambient comfort in sticky weather,” she explained.
Blyss A018I-09C 9000BTU portable air conditioner
If you’re keen to spend less, the Blyss A018I-09C 9000BTU portable air conditioner was chosen as our best budget model. “If you want a straightforward, no-fuss air conditioner that still gives you a bit of flexibility, this Blyss model is a solid option,” noted Joanne Lewsley in her Blyss air conditioner review.
“It covers the basics well, with cooling, fan and dehumidifier modes, plus three fan speeds and a 24-hour timer to fine-tune things depending on how you’re using it – and it’s good value,” she wrote.
Want more warm-weather essentials? Check out the best air coolers
