Best Window Heat Pumps 2026: Which Ones Really Heat in Winter

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It’s a chilly October evening in the apartment. The radiator clanks, one bedroom is too hot and the other is freezing, and the window AC that kept you sane all summer is just sitting there. A window heat pump looks the same from the street, but it runs in reverse in cold weather, pulling heat from outside and blowing it into the room. The question that matters is how cold it can get outside before it stops.

The best window heat pump for real winter heat is the Gradient All-Weather 120V: it plugs into a regular outlet, heats down to -13°F, and still delivers 7,200 BTU/h at 5°F. For spring and fall heat at a much lower price, the Midea 12,000 BTU Smart Inverter Window AC with Heat works well, but its heat pump stops below about 41°F outside.

That split is the whole story of this category: a few cold-climate window heat pumps that can heat a room through winter, and many “AC with heat” units that only heat in mild weather. Below we sort them honestly, with real specs from the makers, and point you to a mini split when you need more. We researched and compared them from maker spec sheets, manuals and program reports; we did not test them.

Prices change often. The prices below are what we saw at the maker or a major retailer in October 2026; check the current price before you buy. Two of these units have no public price at all.

Our top picks

Window heat pumps compared

Unit	Type	Heats down to (outside)	Heat at 5°F	Power	About (Oct 2026)
Gradient All-Weather 120V	Saddle window heat pump	-13°F	7,200 BTU/h (COP 2.06)	120V outlet	Quote (earlier MSRP reported at $3,800)
Midea PWHP	Packaged window heat pump	-22°F	100% of rated capacity (COP up to 2.0)	120V/15A	Distributor quote
Midea 12K Window AC with Heat	Window AC with heat pump	About 41°F	None (heat pump off)	115V	Check price
Midea Duo 14K	Portable, two hoses	41°F	None (heat pump off)	115V	Check price
MRCOOL DIY 12K	Ductless mini split	Not stated on the pages we read	Not stated	115V	$2,158 (retailer sale)

Winter heat vs “shoulder-season” heat

Every heat pump gets heat from outdoor air, and the colder that air, the harder the job. Ordinary window units with a heat pump are built like window ACs run backward. Midea’s 12,000 BTU window model, for example, is sold for “supplemental heat for spring and fall” and its heat pump won’t run below about 41°F outside, to keep the outdoor coil from icing. Midea’s Duo portable manual lists its heat pump range as 41°F to 86°F. Those units are great for cool mornings in October and April, and useless on a January night.

Cold-climate window heat pumps are a newer, different machine. Gradient’s All-Weather 120V lists heating capacity down to -13°F, and Midea’s Packaged Window Heat Pump uses a vapor-injection compressor that Midea says keeps 100% of its heating capacity at 5°F and keeps running to -22°F. Both were picked for New York’s Clean Heat for All Challenge, run by NYSERDA, NYCHA and NYPA to replace steam heat in public housing; Governor Hochul’s office announced the first installations in September 2023.

Why it saves money (an estimate): a plug-in space heater turns 1,500 watts into about 5,100 BTU/h of heat, a coefficient of performance (COP) of 1. Gradient’s spec sheet lists 7,200 BTU/h at 5°F with a COP of 2.06, which works out to roughly 1,000 watts of electricity for 40% more heat than a 1,500-watt heater. At 47°F its COP is 4.04, so the same heat costs about a quarter as much as resistance heat. Your results depend on the room, the weather and your rate.

Not heat pumps: GE Profile ClearView and Windmill

Two popular window units often show up in “window heat pump” searches and they don’t heat at all. The GE Profile ClearView is a saddle-style window air conditioner that looks a lot like a window heat pump, but none of the ClearView models we found has a heat mode. Windmill sells cooling-only window ACs. Both are fine air conditioners; if cooling is all you need, see our best energy-efficient air conditioners. Just don’t count on either one to warm a room. Watch also for window ACs sold “with heat” that use an electric heating element instead of a heat pump: they heat in any weather, but at the same cost per hour as a space heater.

The best window heat pumps

1. Gradient All-Weather 120V: best for winter heat

The Gradient saddles over the windowsill, with half the unit inside and half outside, so the window can still close most of the way and you keep your view. Gradient lists 9,300 BTU/h of cooling (EER 13.6) and 9,000 BTU/h of heating at 47°F, 7,200 BTU/h at 17°F and 5°F, and 7,026 BTU/h at -13°F, its lowest operating temperature. It plugs into a standard 120-volt outlet with a 6-foot cord, is ENERGY STAR certified, runs at 38 to 47 dB(A) and has app scheduling. It weighs 140 lb and needs a window at least 26 inches wide; Gradient says two people can install it. Gradient’s shop shows no price or cart in 2026 and asks buyers to contact sales; press reports put the earlier MSRP near $3,800.

• Good: real heat well below freezing from a plug-in window unit; quiet; no line sets or outdoor pad.
• Watch out: no public price; at 140 lb it’s a two-person lift; about 9,000 BTU/h heats one room, not an apartment.
• Best for: renters and condo owners in cold places who can’t install a mini split.

See it at Gradient

2. Midea Packaged Window Heat Pump (PWHP): best for buildings

Midea calls the PWHP a window-mounted cold-climate air-source heat pump. It uses an EVI (vapor injection) compressor, and Midea says it keeps 100% of its heating capacity at 5°F with a COP up to 2.0 and keeps running down to -22°F. Its ratings are CEER 17.6, SEER 19.0 and HSPF2 10.12, on a 120V/15A circuit, and it uses a saddle shape to manage condensate. It isn’t sold in stores: Midea asks buyers to contact its authorized distributors for pricing, and it’s mostly used in building programs like New York’s. Midea doesn’t list a model’s BTU rating on the page we read.

• Good: the lowest operating temperature in this guide and strong efficiency ratings.
• Watch out: no retail channel, no public price, capacity not on the maker page.
• Best for: landlords, co-ops and housing programs replacing steam or baseboard heat across many apartments.

See it at Midea

3. Midea 12,000 BTU Smart Inverter Window AC with Heat: best for spring and fall

This is the window unit to buy if you want efficient cooling all summer and a cheap way to take the chill off on mild days. Midea rates it at 12,000 BTU of cooling for up to 550 square feet, as low as 45 dBA, and says its inverter uses 35% less energy than the DOE minimum CEER. It cools, dehumidifies, ventilates and heats, with app and voice control. The heat is “supplemental heat for spring and fall,” in Midea’s words: the heat pump doesn’t run when it’s below about 41°F outside, and the Midea page we read lists no heating BTU rating or backup heater. It weighs about 58 lb and has a one-year warranty. Note: this is not the U-shaped Midea, which has no heat.

• Good: efficient inverter cooling plus heat pump heat on cool spring and fall days; easy to find.
• Watch out: no heat pump heat below about 41°F; heating capacity not published on the page we read; one-year warranty.
• Best for: mild climates, or as a shoulder-season helper so the furnace or boiler can stay off longer.

Check the Midea 12,000 BTU Window AC with Heat price on Amazon

4. Midea Duo 14,000 BTU Portable AC with Heat Pump: best portable

Some windows can’t hold a window unit: casements, sliders, building rules. The Midea Duo is a portable unit with a hose-within-a-hose design that pulls outdoor air in and sends it back out, rated 14,000 BTU (ASHRAE) or 12,000 BTU (SACC) of cooling for up to 550 square feet on 115 volts. Its heat pump mode works when it’s 41°F to 86°F outside, per Midea’s manual, and in heat mode you must connect the drain hose, because the unit makes condensate. It’s another shoulder-season heater, not a winter one, and Midea lists a one-year warranty.

• Good: fits windows a window unit can’t; heat pump heat on mild days; app and voice control.
• Watch out: no heat pump heat below 41°F outside; heat mode needs a drain hose; portables take floor space.
• Best for: renters with sliding or casement windows in mild climates.

Check the Midea Duo price on Amazon

5. MRCOOL DIY 5th Gen 12K: best upgrade for all-winter heat

If you own the place and want heat all winter without a quote for a cold-climate window unit, a ductless mini split is the next step. MRCOOL’s DIY 5th Gen 12K (115V) is rated SEER2 23.5 and HSPF2 10.2 in Region IV (7.6 in Region V), comes with a 25-foot pre-charged line set, and MRCOOL allows homeowner installation without voiding the warranty (7 years on the compressor, 5 on parts). It still means a hole through the wall for the line set and an outdoor unit on a pad or bracket, and the dedicated circuit is work for a licensed electrician, with a permit where required. A retailer had it on sale for $2,158 (regular $2,891).

• Good: real whole-season heating and cooling for a room or open area; no refrigerant work for the homeowner.
• Watch out: a permanent install, not for most renters; we didn’t find a minimum heating temperature on the pages we read.
• Best for: homeowners who want one room or a finished basement heated through winter.

Check the MRCOOL DIY 12K price on Amazon

How to choose a window heat pump

• Find the lowest outdoor temperature. This is the number that decides everything. If your winters dip below 40°F, a 41°F unit is a spring-and-fall heater only; look for a cold-climate model with a stated capacity at 5°F.
• Read “heat” carefully. “Heat pump,” “heat” and “electric heat” are not the same. Electric heat strips work in any weather but cost as much to run as a space heater; cool-only units like the GE Profile ClearView and Windmill don’t heat at all.
• Size for the room. Makers rate cooling by square feet. For heating, check the BTU/h at your cold-weather temperature; Gradient’s 7,200 BTU/h at 5°F is about the output of one-and-a-half 1,500-watt heaters.
• Check the window and the weight. Gradient needs a window at least 26 inches wide and weighs 140 lb. Ask your landlord or building about window-unit rules and safe brackets.
• Plan for water. Heat pumps make condensate in heating mode too. Portables need a drain hose in heat mode; saddle units manage it outside.
• Look for rebates. The federal 25C heat pump credit ended for work completed after December 31, 2025. Some utilities and state programs pay for ENERGY STAR or cold-climate heat pumps: check your utility, the ENERGY STAR Rebate Finder and DSIRE.

Keep exploring

Our heat pumps guide explains how heat pumps work and whether they’re worth it. For whole-room winter heat, compare the best DIY mini splits and the best heat pumps for cold climates, or see heat pump vs air conditioner. To control a window unit from your phone, read the best smart thermostat for a mini split. The physics is in thermal energy, and the whole section lives under heat pumps.

Window heat pump questions

What is the best window heat pump in 2026?

For heat in real winter weather, the Gradient All-Weather 120V: it plugs into a regular outlet, lists 7,200 BTU/h at 5°F and runs down to -13°F, though Gradient now sells it by quote. For efficient cooling plus mild-weather heat at a store price, the Midea 12,000 BTU Smart Inverter Window AC with Heat, which heats only above about 41°F outside.

Do window heat pumps work in winter?

Only cold-climate models do. Gradient’s All-Weather 120V heats down to -13°F and Midea’s Packaged Window Heat Pump down to -22°F. Most “window AC with heat pump” units, including Midea’s 12,000 BTU window model and the Midea Duo portable, stop heating below about 41°F outside, so they’re for spring and fall.

Is the GE Profile ClearView a heat pump?

No. The GE Profile ClearView is a saddle-style window air conditioner that cools only; none of the ClearView models we found has a heat mode. Windmill’s window units are also cool-only. They’re good air conditioners, but they won’t heat a room.

Is a window heat pump cheaper to run than a space heater?

When it’s running in its range, yes. A space heater has a COP of 1. Gradient lists a COP of 4.04 at 47°F and 2.06 at 5°F, so by our estimate it uses about a quarter to half the electricity of a space heater for the same heat. Below its cut-off temperature, a mild-weather heat pump gives you no heat at all.

Can I install a window heat pump myself?

Window and portable units plug into a regular outlet and install like a window AC; Gradient says two people can install its 140 lb unit. Follow the maker’s bracket and window rules, and check your lease. A mini split is a bigger job: MRCOOL’s DIY line allows homeowner installs, but the circuit belongs to a licensed electrician.