Garden 
Affiliate Disclosure
Some links on this page are affiliate links. As an Amazon Associate, we earn from qualifying purchases — at no extra cost to you. We do not buy, test, or physically handle the products we cover; our rankings come from aggregated owner reviews, ratings and expert consensus. Commissions never change our verdicts. How we rank · full disclosure.
The short answer: yes, relative to the cooling they deliver. A portable air conditioner draws 700 to 1,600 watts while cooling — about $0.12 to $0.27 an hour at the US average residential rate of roughly 17 cents per kWh (EIA). The problem is efficiency, not raw draw: portables typically rate CEER 7 to 9 against 11 to 15 for comparable window units, so they use 30 to 50 percent more electricity for the same cooling. Used to cool one occupied room, that is still cheaper than running central air for the whole house.
We do not physically handle the products we rank; picks come from aggregated owner reviews and expert consensus — see how we rank. Shortlists are in best portable air conditioner.
What does a portable AC cost to run per month?
Take the running wattage, multiply by hours, divide by 1,000, and multiply by your electricity rate. The figures below assume continuous compressor operation, which is the worst case — a unit that is correctly sized for the room will cycle off and land 20 to 40 percent below these numbers. Rates vary widely by state, from around 11 cents per kWh in the Pacific Northwest to over 30 cents in California and parts of New England, so check your own bill.
| SACC rating | Running watts | Per hour at 17¢ | 8 hours (one night) | 8 h/day for 30 days |
|---|---|---|---|---|
| 6,000 BTU | 650 – 800 W | $0.11 – $0.14 | $0.88 – $1.09 | $26.52 – $32.64 |
| 8,000 BTU | 850 – 1,050 W | $0.14 – $0.18 | $1.16 – $1.43 | $34.68 – $42.84 |
| 10,000 BTU | 1,050 – 1,250 W | $0.18 – $0.21 | $1.43 – $1.70 | $42.84 – $51.00 |
| 12,000 BTU | 1,250 – 1,450 W | $0.21 – $0.25 | $1.70 – $1.97 | $51.00 – $59.16 |
| 14,000 BTU | 1,400 – 1,650 W | $0.24 – $0.28 | $1.90 – $2.24 | $57.12 – $67.32 |
| Fan only | 60 – 130 W | $0.01 – $0.02 | $0.08 – $0.18 | $2.45 – $5.30 |
Note that SACC, not the larger ASHRAE number on the box, is the honest capacity figure. Since 2019 the Department of Energy has required portables to publish seasonally adjusted cooling capacity, which accounts for the hot air that leaks back into a room. A unit marketed as 14,000 BTU is frequently 8,500 to 10,000 BTU SACC.
Why are portables less efficient than window units?
Because of where the machine sits. In a window unit the hot condenser coil is outdoors and the cold evaporator coil is indoors, separated by the window frame. In a portable, both coils are inside the room, connected to the outside by nothing but a thin plastic hose that radiates the heat it is meant to be exporting. That heat comes straight back into the room the unit is cooling.
- Single-hose negative pressure. A single-hose portable exhausts room air outdoors, and that air is replaced by hot outdoor air infiltrating through every gap in the house. This is the largest single penalty.
- Uninsulated exhaust hose. A bare hose can sit at 120 to 140°F and behaves like a small radiator in the room.
- Leaky window kits. The accordion panel supplied with most units seals poorly, especially on sliding windows.
- Dual-hose designs fix the first item and are meaningfully better — the comparison is in single vs dual hose.
How do I cut the running cost?
Seal the window kit properly first — it is free and it is the biggest gain available. Foam-tape the perimeter of the panel, block the open accordion slot on a sliding-window kit, and stop the unit fighting its own exhaust. Insulating the hose with a purpose-made sleeve is the second cheapest improvement. After that: keep the hose short and straight, clean the intake filter every two weeks in season, and close blinds on sun-facing windows during the day.
Adding a ceiling fan lets you hold a higher setpoint — the Department of Energy puts that at about 4°F with no comfort loss, which is a far larger saving than anything you can do to the AC itself. Bedroom-specific picks are in best portable AC for a bedroom, and the window-unit comparison is in portable AC vs window AC. If yours is drawing power without cooling, start at why is my portable air conditioner not cooling.