10 best portable air conditioners to keep you cool in the summer, tried and tested

The summer heat might seem great when you’re lounging around outside, getting a gorgeous golden tan, but it’s likely to become unbearable when you head indoors. Even with a wet towel draped over your body, the windows open wide and tower fans on full blast, it still might not be enough to cool you down. That’s where the best portable air conditioners come in.

When the temperature rises, the most effective solution for overcoming the heatwave blues is an air conditioner. Unlike fans, which simply circulate hot air, air conditioners extract the hot air from your room and replace it with a refreshing cool blast instead.

However, wall-mounted air conditioners are expensive, and, chances are, you’re mainly going to be using them for mini heatwaves, which come in spurts throughout the summer here in the UK. You’re not going to be using one enough throughout the year to make them worth the cost of installation, making portable air conditioners (PACs) a more cost-effective solution.

Portable air conditioners can be carted from bedroom to office to living room, and they can be easily packed away and stored for the winter. All PACs are vented via a duct through a window or wall – the hot air needs to go somewhere to get it out of your home. While most of them come with window kits to make them as energy-efficient as possible, they’ll really only work with sliding or sash windows. You’ll most likely have your window wide open whenever you use a PAC, so bear that in mind.

It’s also worth noting that, while they’re technically portable, PACs are large machines, because of all the engineering inside. There’s an evaporator, a condenser and a compressor. They’re heavy, but they offer a sure-fire way to cool down a room. Air conditioners are measured in British Thermal Units (BTUs) – the higher the BTU, the more powerful the portable air conditioner. 

A portable air conditioning unit with 7,000 BTUs will cool a small room of around 18 to 20 square metres, but always check the size of the room before you buy. A unit with too low a BTU for the space won’t cool it effectively.

How we tested the best portable air conditioners

We reviewed a range of portable air conditioner units in our homes – in