One of the essential home appliances you have in your furnace, so the maintenance you perform is critical to its lifespan. Along with regular tune-ups and cleaning comes the replacement of the furnace filter. It is essential to know that not all furnace filters are made equally, which may not work best for all furnace types.

When it comes to comparing furnace air filters, you want to focus on size, efficiency ratings, and the material of the filter.

Read on to learn how different furnace air filters compare to one another.

Why Compare Furnace Air Filters?

You may be wondering why you should even go through the process of comparing furnace air filters. After all, they all seem to serve the same purpose, which is to capture impurities from the air, so they don’t get circulated in the room. While this may be true, there are different things you need to know about furnace air filters to ensure the proper function of your furnace.

Types of Furnace Air Filters

There are many different types of furnace air filters you can purchase, so you must understand each type.


Many people choose to use fiberglass or synthetic furnace air filters because they are inexpensive and readily available. You can find these filters at any store that has air filters. When you look at this type of filter, you will notice it is relatively thin and have large pore spaces in the filter.

This type of filter does a nice job of stopping large dust particles from circulating your home and building upon the furnace motor and components. However, fiberglass and synthetic filters allow smaller particles to circulate the house, so they may not be the best choice for allergies or sensitivities to dust and dander.

(Source: US Home Filter)


Electrostatic furnace air filters are popular because they don’t have to be discarded after use. They are known as washable air filters. Because they are reusable, electrostatic filters may be more economical over time if they are adequately maintained. Although these filters are reusable, they may not be the best bet for those with respiratory conditions because they may not filter out the tiny particles that irritate.

If you choose to use an electrostatic furnace air filter, you need to be regimented when maintaining and cleaning the filter. Failure to clean the filter frequently will lead to excess dust and could cause problems with the function of your furnace.
(Source: Simply the Best AC)

Pleated Paper

You have likely seen the more common pleated air filters in stores. These filters come in various thicknesses, so you can adjust the filtration levels by replacing the filter. They are often made with paper layers that are pleated and placed in a cardboard frame. Unfortunately, pleated filters are not reusable and can have negative impacts on energy usage in your home.

Because the filters are tightly woven, the airflow is much more restricted, which causes higher energy usage and a more significant strain on your furnace system. The appealing part of these filters is that they can be customized for your air quality needs and are most helpful for those with severe allergies and asthma.

(Source: LA Heating and Air Conditioning)


Polyester furnace air filters are more economical than some options but require frequent changes to ensure they properly maintain the air quality in your home. There are different levels of polyester air filters you can choose from, but you must know they may not filter out all of the small dust and dander particles that cause respiratory issues.

Which Air Filter Is Best?

After seeing all of the options on the market for furnace air filters, you may be wondering which is the best option to choose. Unfortunately, there isn’t one way to determine the very best filter for your furnace. When selecting a filter for your furnace, here are some things to consider.

Budget: As with any purchase, you want to keep your budget in mind. If you choose the least expensive air filter, you may be subjecting your furnace to added stress which could cost more in the long run. When considering your budget, you also need to factor in how that number may impact the life expectancy of your furnace.

Health Needs: The air filter in your furnace can directly impact the respiratory health of you and your family. If you have respiratory issues, you will likely want to look at a higher-quality filter that won’t allow small particles to disperse into your home.

Time: Think about the amount of time you have to devote to changing and monitoring the filter in your furnace. If you can be disciplined in changing the filter at specific time increments, you may be able to get away with using a lower-cost filter. However, if you cannot devote the proper time to monitoring and changing the filter, you may want to choose a more durable and longer-lasting filter.

Furnace Type: Not all furnaces are equipped to handle heavy-duty air filters. If you try to put a HEPA filter into a basic residential furnace, you could cause extreme damage to the furnace motor. Because HEPA filters greatly restrict the airflow into the furnace, you could cause irreversible damage.

Size: Furnace air filters come in a variety of sizes. You must know the proper size for your furnace, or the filter will not work correctly. Although a smaller filter will fit into your furnace, it will not properly filter out the dust particles to keep your air safe. On the opposite side, if you put a filter that is too large into your furnace, it won’t allow the furnace to close properly and will impact the amount of filtration. (Source: HVAC Boss)

Final Thoughts

Choosing the proper furnace air filter can be an overwhelming task, but it doesn’t have to be. When choosing an air filter for your furnace, make sure you select the correct size and filtration level for your needs and the safety of your furnace. Whether you choose disposable or reusable air filters, all have pros and cons that you need to weigh based on your needs. If you are uncertain about the type of filter you need, you can reach out to an HVAC tech for guidance.


company icon