Portable Air Conditioners: What to Buy and What to Pay

A portable air conditioner is the go-to option when a window unit is not allowed, your windows are an awkward shape, or you need to cool a room that central air does not reach. They are easy to set up, but they are also easy to get wrong. Here is what actually matters, how much to pay, and when to buy.

Portable or window unit?

Be honest about this first. Window air conditioners are usually cheaper, quieter and more efficient than portable units of the same rating, because the hot parts sit outside. A portable AC makes sense when:

your lease, HOA or building rules ban window units
you have casement or crank windows that will not hold a window unit
you want to move cooling between rooms

Size it to your room

An underpowered unit runs constantly and still fails to cool. Since 2017, US portable ACs show two ratings: the older ASHRAE figure and the lower, more realistic SACC (seasonally adjusted cooling capacity). Use the SACC number when comparing. As a rough guide:

Up to about 300 sq ft: 6,000 to 8,000 BTU (SACC).
300 to 500 sq ft: 8,000 to 10,000 BTU (SACC).
500 sq ft and up: 10,000+ BTU, or consider a window, ductless mini-split or second unit.

Size up for sunny rooms, top floors, kitchens and high ceilings.

Single hose vs dual hose

Single-hose units pull air from the room to cool their own parts and blow it outside, which draws warm air in through gaps around doors and windows. Dual-hose units take that air from outside instead, so they usually cool faster and more evenly in hot weather. If you live somewhere with long, hot summers, a dual-hose or inverter model is worth the extra cost.

Noise matters more than you think

Portable units keep the compressor inside the room, so noise is the most common complaint. If you plan to run it in a bedroom, look for a sleep mode and published decibel figures, and check reviews for noise specifically. Inverter models, which slow down rather than switching on and off, tend to be quieter and more efficient.

Get the installation right

Check that the included window kit fits your window type, whether sliding, double-hung or casement.
Keep the exhaust hose as short and straight as possible; long or kinked hoses cut cooling noticeably.
Seal gaps around the window panel with foam strips.
Check how condensate drains. Many units evaporate most of it, but in humid climates you may need a drain hose.

Running costs

A typical 10,000 BTU portable unit draws around 1,000 watts. At the US average electricity rate of about 17 cents per kWh, running it for 8 hours costs roughly $1.35 a day, or around $40 a month. Rates vary a lot by state, and inverter models can cost noticeably less to run. Closing blinds on sunny windows and cooling only the room you are using both help.

What you get at each price

$250 to $400: single-hose units for bedrooms and small offices. Fine for occasional use in moderate climates.
$400 to $600: stronger dual-hose units, better window kits, Wi-Fi app control and quieter operation.
$600 and above: inverter units with the best efficiency and lowest noise, and heat pump models that also heat in winter.

When to buy

Prices are highest in early summer, when heat waves drive demand and stock sells out. The best deals usually arrive in late summer and fall clearance, and on Black Friday, so buying in the off-season is often the smartest move. Compare current prices across retailers on sales365days and check our Sale page. Photo: Unsplash. Affiliate disclosure: sales365days may earn a commission when you buy through links on this page, at no extra cost to you. This does not affect the prices we show or how we rank products.