10 Best Under 300 Portable Air Conditioners of 2026

There isn’t a single ‘best’ unit for everyone — the best portable AC under £300 in 2026 depends on your room size, noise tolerance and desired features. Popular choices tend to offer around 7,000–11,000 BTU, a decent EER, straightforward window‑kit installation and reliable aftercare from UK retailers like Currys, Argos or AO.

Portable ACs are worth it if you need targeted cooling in a rented property, a single room, or temporary cooling without installing a fixed unit. For whole‑house cooling they’re less suitable and running costs can be high, so weigh upfront price (under £300) against likely electricity use.

Value is a balance of cooling capacity, efficiency, noise and build quality — units that deliver around 8,000–11,000 BTU with a good EER and included window kit typically offer the best value under £300. Look for models from reputable brands sold through UK stores with a clear returns policy and warranty.

De'Longhi often focuses on build quality and quiet operation, while Honeywell models tend to be competitively priced and widely available in the UK. Choose De'Longhi for quieter, premium feel if it fits your budget; pick Honeywell for solid performance at a lower price — always compare specific model specs (BTU, noise, EER).

Measure the room’s floor area and use the manufacturer’s BTU guide — as a rough rule: small rooms up to ~15 m² need around 7,000–8,000 BTU, medium rooms 15–25 m² around 9,000–12,000 BTU. Adjust upward for very high ceilings, lots of sun exposure, or multiple occupants.

Most portable air conditioners sold in the UK will plug into a standard 13A household socket, but check the unit’s power draw (watts) before purchase to ensure your circuit won’t be overloaded. Avoid running other heavy appliances on the same circuit when the AC is running.

You can find models under £300 at UK retailers such as Currys, Argos, AO, John Lewis and Amazon UK, plus direct from some manufacturers’ UK websites. Look for seasonal sales and check the retailer’s returns, delivery and warranty terms before buying.

Yes, single‑hose units can be less efficient because they draw in warm air from the room to feed the exhaust, creating slight negative pressure and letting warm air in. Dual‑hose models, which use a separate intake from outside, are typically more efficient — though true dual‑hose options are rarer under the £300 price point.