Portable AC vs Window AC: Which Is Better? (11-Point Comparison)

Person A: “Portable AC units are better than window AC units.”

Person B: “No, I’ve bought a window AC unit and it’s much better than a portable air conditioner.”

Which unit is actually better: portable or window AC? As you might imagine, many people have an established opinion when it comes to window vs portable AC units. Others don’t really have a clue how to even begin comparing portable AC units to window AC units.

Some say that portable AC units are better than window AC units, others claim they have never had a problem with window AC and therefore it must be better than a portable AC.

You cannot adequately base your decision on whether to choose a window or portable AC unit only on opinions. You should base it on facts. Luckily, in HVAC worlds, we can describe a lot of performance parameters with pure numbers (metrics, if you will).

That’s why we have made a complete 11-point head-to-head specs-based comparison of window vs portable air conditioners. We will delve into the most important factors, including energy efficiency, noise levels, expected lifespan, installation difficulty, prices, and so on.

Just to give you some perspective: In 2019 alone, 8.49 million room air conditioners were sold in the US. The majority of these were either portable or window AC units.

Note: For the final resolution on which is better – portable AC unit vs window unit – we have to understand that this is not a definitive black and white issue. For some homeowners, a portable AC unit is a better choice. Others will benefit more by installing a window AC unit on their window sill.

Let’s start by summarizing all the main differences between portable and window AC units. After that, we will look deeper into each difference and explain why it matters and what kind of importance you should give to let’s say energy efficiency or lifespan.

We also include hints on how to overcome the cons of both portable and window AC units and how to focus on the pros:

Portable Air Conditioner Vs Window Unit (Summary Of 11 Differences)

There are quite a few similarities between portable and window units. These are both room air conditioner types, require no ductwork, are very easy to install, require minimum maintenance, don’t break down a lot, and are not fixed (can be moved from room to room).

However, to actually compare window vs portable AC units, we need to focus on specific differences between these two types of AC units. Here is a complete list of 11 differences between portable and window AC units (we will look into each of these 11 differences more thoroughly further on):

Specification: Portable AC Unit: Window AC Unit:
1. Energy Efficiency Lower (Average 8.5 EER Rating) Higher (Average 10 EER Rating)
2. Noise Levels Slightly Higher (55-60 dB) Slightly Lower (53-58 dB)
3. Cooling Capacity And Room Coverage Narrower Range (8,000 – 14,000 BTU; 200-700 sq ft) Wider Range (5,000 – 25,000 BTU; 150-1,250 sq ft)
4. Expected Lifespan Shorter (5-10 Years) Longer (10-15 Years)
5. Installation Difficulty Slightly Easier Slightly Harder
6. Voltage Requirements: What Kind Of Electric Circuit Do You Need? Standard 110/120V Circuit 110/120V (15,000 BTU And Below) And 220/240V (More Than 15,000 BTU)
7. Space Requirements: How Much Space Does It Take? Up To 20″ x 20″ Room Space, With Up To 40″ Height (Takes Some Space) Adequately Sized Window Sill With Up To 20″ Height (Limits Natural Light)
8. Venting Requirements Hose Through The Opened Window No Additional Venting Required
9. Installation Kit Window Seal (Harder To Install) Window Seal (Easier To Install)
10. Portability Easy To Move To Another Room Harder To Move To Another Room
11. Price More Expensive ($300-$800) For 8k-14k BTU Capacity Cheaper ($180-$700) For 5k-25k BTU Capacity

Are window air conditioners better than portable units? Air portable air conditioner better than window units?

Just this overview illustrates that the answer to these questions is not all black and white. There are a lot of nuances is there. That’s why let’s delve into each of the differences between portable AC and window AC units one by one.

We will start with the difference HVAC expert find the most important:

1. Portable AC vs Window Unit: Energy Efficiency (Window AC Is 15% More Efficient)

Energy efficiency is one of the most important specs you would be aware of when comparing portable to window AC units. More energy efficient units have lower running costs. Highly energy efficient AC units can have you several $10 per season; this results in a several $100 difference in 10 years.

On average, window air conditioners are more energy efficient than portable air conditioners. Energy efficiency is measured by the EER rating (and the newer CEER rating). Higher EER and CEER rating equates to lower running costs.

Window AC units have a clear advantage over portable AC units here:

That means that window air conditioners are about 15% more energy efficient than portable air conditioners.

window vs portable ac unit energy efficiency
Due to higher energy efficiency, window AC units require less electricity than portable AC units to run.

As a general rule, you would always invest in a more energy efficient AC unit. By choosing a window AC unit over portable AC unit, you are likely going to save several $100s just on cooling costs.

Hint: If you choose a portable AC unit, invest in dual-hose units. These units have a higher energy efficiency than single-hose units and you don’t run into negative indoor air pressure problems.

Energy Efficiency Winner: Window AC Units

2. Noise Levels (Window AC Units Are Quieter In General)

Portable and window AC units are not split systems. That means that they contain the air compressor – the loudest part of any air conditioner – in the indoor unit (since you only have 1 unit). Mini splits, for comparison, contain the air compressor in the outdoor unit and have lower indoor noise levels (this is explicitly illustrated in our article about the quietest air conditioners for bedrooms here).

When you’re choosing a quiet air conditioner, you have to open the specs sheet and check the noise levels for Low/Middle/High fan speed setting.

Between portable and window AC unit, the window air conditioner are quieter than portable air conditioners (in general). The difference in noise levels is not all that big:

  • At 100% cooling output, window air conditioners produce about 53-58 dB of noise. The quietest window AC units you can check here run at below 50 dB. Example: TOSOT Tranquility 8,000 BTU unit generates 42-49 dB of noise.
  • At 100% cooling output, portable air conditioners produce about 55-60 dB of noise. The quietest portable AC units you can check here run at low 50 dB noise levels with the Frigidaire FHPH132AB1 running at below 49 dB levels.

At such a small difference, you can find a portable air conditioner that runs quieter than a window air conditioner (with the same cooling capacity; say 12,000 BTU) as well.

is portable ac quieter than window ac unit
Illustration of window air conditioner noise levels by Frigidaire.

Nonetheless, in general, window AC units generate less noise than portable AC units.

What you do need to be aware of, in addition to the specified noise levels, is AC unit positioning. Namely, portable AC units are placed on the floor and window AC units are placed on the window.

Due to the elevated positioning of the window units, lower noise levels can be a bit louder. The low position (on the floor) of portable AC units can reduce the noise levels we perceive.

Noise Levels Winner: Window AC Units

3. Window Vs Portable AC Cooling Capacity And Room Coverage Comparison

The capacity of air conditioners is measured in BTU/hr. Bigger rooms will require higher BTUs and smaller rooms will require lower BTUs. You can read all about how to size air conditioners with a BTU calculator here.

According to the robust DOE’s rule of thumb, you need about 20 BTU per sq ft of living space (8 ft ceiling height). That means that the capacity of both window and portable AC units corresponds to the room coverage as well.

When comparing cooling capacity and room coverage, window air conditioner have a much larger range than portable air conditioners:

  • Window AC units can produce anywhere from a very low 5,000 BTU output to a quite big 25,000 BTU cooling output. That means you can use a window air conditioner for cooling spaces from 150 sq ft to up to 1,250 sq ft.
  • Portable AC units have a limited range. They can produce between 8,000 BTU to 14,000 BTU cooling output. That means they can be cool spaces from 200 sq ft to up to 700 sq ft.

This simply means you can use window AC units for smaller and very large rooms.

Small Rooms: If you check the smallest air conditioner here, you can find 5,000 BTU window AC units (these can even cool small 10×10 or 12×12 rooms). If you check for the smallest portable units, the lowest BTU output you will find is 8,000 BTU (for 200+ sq ft rooms).

Big Rooms: The biggest portable AC units generate 14,000 BTU of cooling output. Compares to 14,000 BTUs, the biggest window AC units you can find here can generate up to 25,000 BTU. That means that you are looking at 700 sq ft vs up to 1,250 sq ft coverage for portable and window units, respectively. Window AC units have more cooling power than portable AC units.

All in all, the choice of window AC units on the market provides you with a much larger range of cooling capabilities than the portable air conditioner.

Cooling Capacity And Coverage Winner: Window AC Units

4. Expected Lifespan (Window AC Units Last Longer Than Portable AC Unit)

One of the key differences between portable and window AC units is how long they last. Obviously, you would prefer the air conditioner to last as long as possible.

In regards to the expected lifespan, the window air conditioners have a clear advantage over portable AC units. That’s because:

  • Window air conditioners last from 10 to 15 years. It’s very common to find a 10+ year-old window AC.
  • Portable air conditioners last from 5 to 10 years. It’s rather uncommon to find a 10+ year-old portable AC.

This means that, on average, window AC units last about 5 years longer than portable AC units. In short, they are more durable. You can read all about how many years do different types of air conditioners last here.

You also have to be aware of how the lifespan of an air conditioner affects how you look at the cost of an AC unit.

Example: If a window AC unit with a 12.5-year average lifespan costs $500, you are basically paying $40 per year for the unit. If, on the other hand, a portable AC unit with a 7.5-year average lifespan costs $500, you are paying $67 per year for the unit.

Window AC units being more durable than portable AC units is another point for window units.

Lifespan Winner: Window AC Units

5. Installation Difficulty (Portable AC Units Are Easier To Install Than Window Units)

In many cases, the portable vs window AC units dilemma comes down to comfortability. A big part of that is how easy it is to install an air conditioner.

Both window and portable air conditioners have an easy installation process. In fact, pretty much everybody installs these room air conditioners themselves. You don’t need a professional HVAC installation like with mini splits or central AC units.

Comparatively, it’s a bit easier to install a portable air conditioner than a window air conditioner.

Here is how easy it is to install a portable AC:

  • Carry the unit to a room where you want to use it (these units weigh 50+ lbs, you need strong hands). Set in on the floor.
  • Plug it in a 110/120V outlet.
  • Open a window and vent the hose out of the window.
  • Use the window seal kit (we’ll address till later on) to seal off the window.
  • Press ‘On’ and enjoy the cooling breeze.

Installing a window AC units involves setting it up on the window sill. That’s a bit harder, and you will have to use the window kit to seal the window on the left and the right.

In short, both these room air conditioning units are easier to set up. You will need about 10 minutes for a portable AC unit and 15 minutes for a window unit.

Easier Installation Winner: Portable AC Units

6. Voltage Requirements (Portable AC Requires Only Standard Voltage, Window AC Might Require 220/240V)

Everybody has a 110/120V standard electrical circuit in their home. Not everybody has a 220/240V circuit. As far as the voltage requirements are concerned, you won’t have to upgrade it for portable AC units. For bigger window AC units, however, you will have to upgrade to 220/240V voltage.

Here’s the deal:

Most room air conditioners with 15,000 BTU cooling capacity or less can run on a standard 110/120V circuit. This primarily has to do with electric breakers. We use 15 amp or 20 amp breakers in our homes.

portable ac vs window ac units voltage requirements
An air conditioner with up to 15,000 BTU cooling effect runs on a standard 110/120V circuit.

A 15,000 BTU air conditioner with a 10 EER rating draws 15 amps on a 110/120V circuit (and requires a 20A breaker). A 24,000 BTU window AC unit, for example, will always need 220/240V voltage. If it were to run on 110/120V, it would draw 20+ amps which will fry 15A or 20A standard breakers.

portable vs window ac unit voltage requirements
Bigger 15,000+ BTU window air conditioners will require 220/240V. This is a security measure that prevents your amp breaker from frying.

As you can see, it all comes down to cooling capacity:

  • Portable air conditioners always run on 110/120V because they produce 8,000-14,000 BTU cooling capacity (below 15,000 BTU).
  • Window air conditioners with 15,000 BTU or less cooling output will also run on a 110/120V circuit. However, bigger 15,000+ to 25,000 BTU window AC units will only run on upgraded 220/240V circuit.

We have explained this rule of thumb in our article about the highest BTU air conditioners you can run on 110/120V circuits here.

This means that you have no worries with portable AC units. You may have worries with window AC units.

Voltage Requirements Winner: Portable AC Units

7. Space Requirements: How Much Space Do Window vs Portable AC Units Take?

Everybody understands that you have to put a room air conditioner somewhere in the room.

Portable air conditioners are simply placed on the floor. That reduces the total square footage of the room by 2-4 sq ft. This is because the cross-section of portable AC units is from 10×10 inches to 20×20 inches. You also have to be aware of the height; a portable AC unit is a 30 to 40-inch high box in your room.

Window air conditioners are another matter entirely. They have a similar volume as portable AC units but you have to mount them on a window sill. Secondarily, that means that you have to have a big and wide enough window. This is usually not the issue.

This is:

Primarily, the biggest concern about mounting window air conditioners is that they reduce the natural light that comes into the room. Most people prefer to get as much natural light in their homes as possible. The window AC unit, however, obstructs a significant part of the window and thereby reduces the natural light coming into the room the window AC unit is in.

Most of us can tolerate having a big box on the floor (portable AC unit). Not everybody likes the idea of a window portable AC unit obscuring the light that should be coming through the window.

In this case, the choice between portable and window AC units is quite simple: Portable units are preferable.

Space Requirements Winner: Portable AC Units

8. Venting Requirements: How Difficult It Is To Vent A Portable vs Window AC Unit?

All air conditioners have to be vented. This is the only way how to achieve the heat/cooling transfer adequately according to the 2nd Law of Thermodynamics.

Window air conditioners are positioned on the window sill. These units are automatically vented; the airflow can enter and exit on the front indoor side as well as on the back outdoor side. It’s a simple design that requires no additional venting.

window ac unit venting vs portable unit venting
Design of a window AC unit. It has a self-venting mechanism; you don’t need an additional hose as is the case with portable AC units.

By contrast, portable air conditioners are not vented by themselves. They need a hose (either single-hose or dual-hose) that vents the hot air out of the window. That requires you to install a hose through the window (you have an additional job).

Of course, the most problematic part of a portable AC unit is venting in situations where you don’t have a window. We have talked a lot about venting options for a portable air conditioner without a window here. We note 5 different options; every one of them is an additional bother associated with portable AC units that you don’t find with window AC units.

All in all, the additional need for venting makes the portable AC units a bad choice compared to window AC units.

Venting Requirements Winner: Window AC Units

9. Installation Kit: How To Seal A Window For Portable vs Window AC Unit?

The usage of both portable and window AC units will require you to have an open window. Of course, as you clearly understand, it’s a bad idea to have an air conditioner running with an open window.

That’s why most portable and window AC units come with the window seal kit included. If the kit is not included, you have to buy it separately yourself. These window seal kits are used to close the rest of the window. You have different window seals for window vs portable units.

In the case of portable AC units, you have to tape the kit over the entire window frame. That’s not the easiest task in the world, especially if you have big and tall windows. You can check some of the best window seals for portable air conditioners here to see what they look like.

In the case of window AC units, on the other hand, you only have to shut off the window opening located left and right of the window AC unit. With a kit that’s quite easily done.

When it comes to installing a window seal, it’s easier to seal off the window with a window AC kit than with a portable AC kit.

Installation Kit Winner: Window AC Units

10. Portability: Which One Is Easier To Move Around?

This is quite an obvious but important difference. Of course, portable air conditioners are more portable than window air conditioners.

The ability to easily move an air conditioner from room to room is quite useful. With this option, you have the ability to cool just the room you are currently in and save quite a lot on your cooling bill.

Window AC units are mounted on window sills. To move them to another room, you have to dismount them and mount them again on an adequately sized window sill in another room. That’s quite a lot of work.

In contrast, portable AC units can be moved around quite easily. You just roll or carry them in another room, plug them in, install the window seal, and turn them on. It’s much simpler than with window AC units.

Portability Winner: Portable AC Units (Obviously)

11. Cost Of Portable vs Window AC Units

Last but not least, you have to compare the costs of portable vs window AC units. In general, window air conditioners are cheaper than portable air conditioners. If you account for a bigger cooling capacity and longer expected lifetime, you can say that window AC units are, in fact, much cheaper than portable AC units.

Here are the general price ranges for both types of room air conditioners:

  • Portable AC units cost between $300 and $800. These are 8,000 BTU to 14,000 BTU units. Obviously, the bigger units are more expensive than the smaller ones.
  • Window AC units cost between $180 and $700. The smallest 5,000 BTU unit might cost only $180. Even the biggest 20,000+ BTU units don’t cost more than $700.

The key here is to understand that the window AC units, in general, produce more cooling effect than portable units if the price is the same.

Example: A $500 portable air conditioner generates 12,000 BTU cooling output. A $500 window air conditioner generates a 20,000 BTU cooling effect. The price might be the same but the cooling capabilities are almost always in favor of window AC units.

If you compare prices of portable vs window AC units per generates cooling effect (BTU to BTU), you will see that window AC units are, in general, cheaper than portable AC units. Of course, there are some expectations if you find a good bargain; we have talked about this extensively in our article about the best cheap portable AC units here.

All in all, window AC units are the true price-performance units, especially compared to portable AC units.

Cheaper Price Winner: Window AC Units

Window AC vs Portable AC: Bottomline

As we have seen, portable and window air conditioners have a number of differences.

Portable AC units are preferable if you’re looking for a comfortable unit with easy installation. They require minimum input on your part. However, they don’t last as long as window AC units and tend to be more expensive (both upfront cost and running costs).

Window AC units are more energy efficient, last longer, and have an overall cheaper price (lower upfront cost and lower running costs). They also come in several different sizes (from the smallest 5,000 BTU to the biggest 25,000 BTU units) and can bring effective cooling to every room if adequately sized. They are, however, a little hard to install and harder to move from window sill to window sill.

All in all, both portable and window AC units are good choices if you have to cool down a room quickly. For the final decision of window vs portable AC, you should go point-by-point and see which specs/installation difficulties are important in your situation and which ones are not all that significant.

We hope that all of this helps if only a bit.

If you have any questions regarding the portable vs window aircons, you can pose them in the comments below and we’ll try to help you out.



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