If you’re a summer hater, or if you just run hot all year long, a working air conditioning unit is essential for making indoor spaces comfortable. If you don’t have central air conditioning, a window AC unit — like this Select-favorite Midea AC unit — might be a solid solution.
But if you live in a small space and don’t want to (or are unable to) use window space, you might consider a portable AC unit. These units, which sit by a window, work by intaking warm indoor air, cooling it, and returning the chilled air to the room. The leftover, hot air, travels through a tube out the window, never to be felt again.
While portable AC units are easier to install, they tend to be more expensive than window units, according to the experts we spoke with. To help guide your search and keep you cool without emptying your wallet, we rounded up some highly rated portable air conditioners for under $400.
Our top picks
- For smaller spaces: Black+Decker 8,000 BTU Portable Air Conditioner
- For larger spaces: Shinco 10,000 BTU Portable Air Conditioner
- Smart controlled: Midea 10,000 BTU Portable Air Conditioner
How we picked the best portable air conditioners under $400
The experts we spoke with educated us on the most important features to look for when shopping for a portable AC on a budget. Using their expertise as guidance, we selected top-rated units focusing on the following:
- Price: We only included portable air conditioning units that cost under $400. We see $400 as a sweet spot for value and brand recognition. While there are many portable ACs on sale for less, they come from less recognizable brands, are typically rated for very small rooms and may use air evaporation rather than air conditioning.
- Room size: We picked portable air conditioners fit for small to medium-sized rooms ranging from 150 to 300 square feet. Portable AC units for spaces larger than 300 square feet typically cost more than $400
- Portability: We only included units with built-in wheels, making them easier to move, relocate and store.
- Top-rated: We only selected portable AC units with at least a four-star average rating from customers on Amazon.
The best portable air conditioners under $400 for 2023
Many of our picks are the same products we recommend in our guide to the best portable air conditioning units, coming from top brands like Black+Decker, Shinco and Midea.
For smaller spaces: Black+Decker
While this Black+Decker unit has a list price of $420, data from Amazon price trackers like camelcamelcamel shows an average price of around $350 over the past year and beyond. It is best suited to smaller rooms like bedrooms and offices up to 150 square feet. Like all of our picks, you can adjust the mode between cool, fan and dehumidify within three operating speeds through the buttons on the unit or via the remote control. It also has a timer, sleep mode and auto mode.
While it comes in a wide variety of sizes and specs, this 8,000 BTU version is the lowest priced. It’s also a best seller on Amazon, with a 4.3-star average rating from over 41,000 customer reviews.
Modes: Cool, fan, dehumidify | Cooling power: 8,000 BTUs | Room size: Up to 150 square feet | Speeds: 3 | Weight: 52.9 lbs. | Dimensions: 15.3 D x 14 W x 24.8 H inches
For larger spaces: Shinco
This portable AC unit from Shinco is affordable and rated for spaces up to 300 square feet. 300 square feet is a good fit for offices, living rooms, guest bedrooms and more. This Shinco has a swing mode that oscillates the fan grille, spreading cool air all around your space.
While this unit is well-suited to larger spaces, light sleepers may want to avoid putting it in bedrooms — some customers on Amazon say it is loud, even on its lowest settings.
Modes: Cool, fan, dehumidify | Cooling power: 10,000 BTUs | Room size: Up to 300 square feet | Speeds: 3 | Weight: 61.6 lbs. | Dimensions: 13.39 D x 17.44 W x 32.68 H inches
Smart controlled: Midea
Anyone looking to get a smart-connected unit for less should check out this portable AC from Midea. It is the only unit on our list that connects to Wi-Fi and has voice controls. Connect the unit with the MideaAir app and control it through your smartphone, Amazon Alexa or Google Assistant.
Outside of smart connectivity, this unit is similar to our other picks, albeit heavier at nearly 68 pounds. It is rated for spaces up to 200 square feet, making it a good fit for a high-tech office or media room.
Modes: Cool, fan, dehumidify | Cooling power: 10,000 BTUs | Room size: Up to 200 square feet | Speeds: 3 | Weight: 67.9 lbs | Dimensions: 13 D x 17.1 W x 28.3 H inches
Most lightweight: SereneLife
Similar to the Shinco unit, this portable AC unit from SereneLife is priced at under $300 and covers over 200 square feet of space. What sets this unit apart from our other recommendations is weight: it is the lightest unit on our list at 46.3 pounds. Its lighter weight is a boon for anyone planning to move their unit around often, especially up and down stairs.
It is basic compared to some of the other units on this list — the remote control does not have a screen and it does not have any smart connectivity. But it has a 4.4-star average rating from over 22,000 reviews on Amazon and is very lightweight compared to the competition.
Modes: Cool, fan, dehumidify | Cooling power: 8,000 BTUs | Room size: Up to 215 square feet | Speeds: 3 | Weight: 46.3 lbs. | Dimensions: 13.8 D x 14.6 W x 27.2 H inches
How to shop for a portable air condition unit under $400
Before you buy a portable AC, you may want to grab your tape measure, measure your space and check for electrical outlets. Learn why below.
BTUs, or British Thermal Units
An AC’s cooling power is measured in British Thermal Units (BTUs): the higher the BTUs, the larger the space the AC can cool. On average, an air-conditioning unit needs about 20 BTUs per square foot of space to keep things cool, says Dr. John McKeon, CEO of Allergy Standards — an organization that, among other things, certifies products as “asthma & allergy-friendly.” To figure out how many BTUs you need for your room size, multiply the square footage of your room by 20.
Below is a breakdown of the number of BTUs needed to cool different-sized spaces. These calculations are averages — it’s still important to refer to the square footage rating referenced on the AC unit itself.
- Up to 250 square feet: 5,000 to 6,000 BTUs
- From 250 up to 350 square feet: 7,000 to 8,000 BTUs
- From 350 up to 450 square feet: 9,000 to 10,000 BTUs
- From 450 up to 550 square feet: 12,000 BTUs
- From 550 up to 700 square feet: 14,000 BTUs
These numbers are not ironclad. Carl Prouty, a tech expert at electronics and appliance retailer Abt, says that you may need more or fewer BTUs depending on what kind of room you are placing the unit in. For a room that gets little to no sun, you can get by with a unit with 10% fewer BTUs than the square footage requirement. For a room that gets sun daily, add 10% more BTUs than required. When shopping for a unit to be placed in a kitchen, add an extra 4,000 BTUs to combat the extra heat produced by kitchen appliances, says Prouty.
Portable AC unit placement
Another thing to keep in mind is placement. Portable air conditioners need to be placed near a window and electrical outlet. You will also need to drain water from the unit, especially if you are using the dehumidifier mode frequently. McKeon recommends draining the water and cleaning the air filters every couple of weeks to prevent mold growth.
Meet our experts
At Select, we work with experts who have specialized knowledge and authority based on relevant training and/or experience. We also take steps to ensure all expert advice and recommendations are made independently and without undisclosed financial conflicts of interest.
- Dr. John McKeon, CEO of Allergy Standards — an organization that, among other things, certifies products as “asthma & allergy-friendly.”
- Carl Prouty is a tech expert at electronics and appliance retailer Abt.
Why trust Select?
Justin Redman is a former reporter at Select on NBC News.
Harry Rabinowitz is a reporter at Select who has covered consumer tech for years. For this piece, he referenced prior interviews with filtration and electronics experts to better understand portable air conditioners and their most important features. He leveraged his personal experience using portable air conditioners in combination with thorough research of customer reviews to select products to recommend.