best furnace filters

Best Furnace Filters to Improve Your Indoor Air Quality

Ian Mutuli
Updated on
Ian Mutuli

Ian Mutuli

Founder and Managing Editor of Archute. He is also a graduate architect from The University of Nairobi, Kenya.
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If you feel like your indoor air quality has suddenly gone down, and maybe your electricity bill has hiked a little, it may be a sign that you need to change your furnace filter. Where can you get a furnace air filter? Well, there are many online shops and home improvement stores that sell the best furnace filters.

There's a lot you probably didn't know about furnace air filters, but by the time you finish reading this article, you will have learned a lot. So get comfortable and be ready to learn.

What is a Furnace Filter?

The first thing you need to know is what a furnace filter is. A furnace air filter is an important device found inside your HVAC (Heating, Ventilation, and Air Conditioning) systems cleaner.

Why should you replace your furnace filters? Well, there are endless reasons for you to get replacement filters. A clean filter cleans the air by trapping dust particles, mold spores, allergens, pet dander, viruses, among other air pollutants.

If you don't replace your filter, you may end up getting higher energy bills, an overheated furnace, or even a damaged blower fan.

What are the Types of Furnace Filters?

There are many types of furnace air filters, and we shall discuss them briefly before we proceed to the best furnace filters.

a). Pleated Air Filter

Pleated air filters can either be disposable or high-efficiency. The disposable pleated air filter traps smaller particles, and they are inexpensive and readily available. On the other hand, high-efficiency pleated filters trap the smallest particles and are very efficient. However, high-efficiency filters are expensive and are not compatible with all types of furnaces as they are thicker.

b). Activated Carbon Filters

Activated carbon filters are among the older types, and they have small absorbent pores that have a chemical reaction when pollutants pass through. Carbon and the pollutants bond during the process, and the carbon filter traps chemicals, smoke, odors, and gasses. Note that you cannot use this filter alone because they do not filter dust or micro-organisms.

c). HEPA

This is the acronym for High-Efficiency Particulate Air. It is a type of air filter that traps up to 99.97 percent of airborne particles up to 0.3 microns and 95 percent success rate for particles as small as 0.1 microns. HEPA filters don't filter odors, smoke, gasses, and chemicals. For full coverage of filter filtration, you can use a HEPA filter with a carbon-activated filter.

d). Disposable Fiberglass

Disposable fiberglass filters are made from spun glass and are great for capturing larger particles. However, you need to dispose of them for efficiency after 30 days; failure to do so, the heating system will have to work extra hard, leading to more energy consumption.

e). Electrostatic Filters

An electrostatic filter is made from self-charging paper of cotton fibers which produce a positive charge. They trap different particles like dirt, dust, and allergens. Most are permanent, but there are washable filters as well. Electrostatic air filters are efficient and, therefore, more costly.

With a clearer understanding of what a filter does and the types available, let us now discuss the best furnace filters.

Five Best Furnace Filters

1. Filtrete AC Furnace Air Filter-MPR 1000

Filtrete 16x25x1, AC Furnace Air Filter, MPR 1000,...
  • DESIGNED WITH EXCLUSIVE Filtrete Brand 3-in-1 technology from 3M...
  • ATTRACTS AND CAPTURES particles such as lint, pollen, dust, pet...
  • 1000 MPR has a rating of MERV 11
  • The higher the MPR, the more microparticles--such as pollen, pet...

This furnace filter by 3M is electromagnetically charged. It is suitable for at-home use as it filters the air by trapping pet dander, lint, pollen, smoke, and smog. It is a highly efficient air filter with a minimum efficiency reporting value of 11.

The exact dimensions of this filter are 24.69 by 0.81 by 15.69 inches. You can get 1000 MPR in 4-inch a slim fit and 5 inches thick filters, so you have different thickness options to choose from. This filter can last for up to three months before changing it.


  • It is marked to show how to insert it into the furnace
  • It is efficient with a MERV of 11
  • Budget-friendly


  • Quality may differ

2. Aprilaire 213 A1 Replacement Air Filter-MERV 13

Aprilaire - 213 A1 213 Replacement Air Filter for Whole...
  • BUY WITH CONFIDENCE This genuine Aprilaire 213 replacement air...
  • CREATE A HEALTHIER HOME by preventing airborne allergens from...
  • BETTER PERFORMANCE thanks to the patented Aprilaire Self-Seal...
  • EASY AS 1-2-3 TO INSTALL in the unique Aprilaire Interlock Rail...

Aprilaire 213 air filter is compatible with various air purifier models, including 1210, 1620, 2210, 2216, 3210, and 4200. It is among the best furnace air filters as it traps most allergens as the air passes through the MERV 13 filter. The filtered particles include bacteria, pet dander, dust mite debris, dust pollen, and mold spores. It also traps unpleasant odors to improve indoor air quality.

It is easy to install in the Aprilaire interlock rail system, and it does not require any assembly, cardboard, or metal reinforcements. This 213 model has a higher rating than the 210 models because it filters smaller particles that the 210 model does not filter.

You can use this filter for up to one year before replacing it. However, if where you live has many pollutants, you may need to replace them sooner.


  • Compatible with multiple Aprilaire systems
  • Traps allergens and odors as well
  • Does not need to be replaced frequently


  • Are only compatible with Aprilaire systems

3. Aerostar MERV 13 Pleated Air Filter

Aerostar 12x12x1 MERV 13 Pleated Air Filter, AC Furnace...
  • Nominal size: 12x12x1; Actual size: 11 3/4"x11 3/4"x3/4"; This...
  • Designed to filter microscopic particles such as lint, dust...
  • Simple to install and a cost-effective step towards a healthier...
  • 100% synthetic electrostatic media for high efficiency with low...
  • Manufactured in the USA by Filtration Group, a world-leading...

This Aerostar is a MERV 13 pleated air filter and comes in packs of six. It filters microscopic particles, including lint, spores, pollen, fine dust, smoke, bacteria, and viruses.

Installation is easy and does not take a lot of your time. Its approximate dimensions are 12 by 12 by 1 inch. This furnace filter requires a replacement every 60-90 days. However, during the peak months like summer and winter, a replacement after 30 days will make it better and more efficient.


  • Filters most airborne contaminants
  • Budget-friendly
  • High minimum efficiency reporting value of 13
  • Ideal for people with allergies


  • Needs to be changed more often

4. Nordic Pure AC Furnace Air Filters-MERV 12

Nordic Pure 16x25x1 MERV 12 Pleated AC Furnace Air...
  • Nominal Size: 16 x 25 x 1, Actual Size: 15 1/2 x 24 1/2 x 3/4...
  • Attracts indoor allergens, dust, pollen and other airborne...
  • Hypoallergenic and antimicrobial pleated electrostatic filter...
  • Nordic Pure recommends changing 1” air filters every 30-90 days
  • Made in the USA

Nordic Pure furnace filter measures approximately 16 by 25 by 1 inch, and it traps pollen, dust mites, dust, indoor allergens, and other airborne particles. It features a hypoallergenic and microbial pleated electrostatic filter material which makes it highly efficient. It also filters unwanted odors, making your home more accomodating.

With this air conditioning filter, contaminated airflow through the MERV 12 filter and clean air flows back, ensuring you breathe in fresh and clean air. The filter requires a replacement every 30-90 days, depending on the number of airborne particles available where you live.


  • It is efficient, with a high MERV of 12
  • Removes particles and odors
  • It is a pack of six


  • Does not filter most odors
  • Slightly smaller

5. Filtrete ADP01 AC Furnace Air Filter- MPR 1000

Filtrete 16x25x4, AC Furnace Air Filter, MPR 1000 DP,...
  • DESIGNED WITH EXCLUSIVE Filtrete Brand 3-in-1 technology from 3M...
  • ATTRACTS AND CAPTURES particles such as lint, pollen, dust, pet...
  • 1000 MPR has a rating of MERV 11
  • The higher the MPR, the more microparticles--such as pollen, pet...

Another great furnace filter by 3M. If you want the best furnace filter, you can't go wrong with this. It traps unwanted particles in the air and releases fresh and cleaner air. It traps particles such as lint, pet dander, smog, smoke, dust, and pollen, among others.

Best filters have high efficiency in filtering smaller particles. This two-pack has MPR 1000, which is the same as MERV 11, and it filters most micro-particles, making it suitable for people with pets.

A dirty furnace air filter will slow down air flow and make the system work extra hard, increasing energy consumption. You can use the Filtrete smart app to choose when you want to change your filter. Once you do that, you will get a reminder to change the filter when necessary. You can use this Filtrete air filter for up to 12 months before it needs a replacement.


  • It is efficient in filtering small particles
  • It is thicker, hence slightly reducing the fan noise
  • Does not require frequent replacements


  • The actual size may be misleading
  • It is hard to remove

What Should You Consider Before Buying the Best Furnace Filter?

Before deciding the kind of furnace filter you want to take home, there are a few factors you will need to keep in mind. Such factors help you make the right decision by ensuring that the filter you buy is the most suitable for you. But, first, let's go through what you need to consider.

a). Type of Filter

As discussed earlier, we have seen the different types of filters available on the market. So, you already know that you have options when it comes to selecting the best furnace filters. Paper and fiberglass are the most economical and the most common. However, you are the only one who knows what's most suitable for you, which will determine the type of filter you select.

b). Filter Size

A furnace air filter will either fit or not. You will get the sizing from your previous filter, which is marked in inches, and these dimensions are given as width by height by thickness. Theoretically, a thicker filter will be more efficient, but they are not interchangeable. So, before buying a filter, ensure that you know the exact size you are looking for to avoid buying one that is too big or too small for the furnace.

c). Compatibility with Furnace

Before buying a furnace filter, you need to check if your furnace only needs a specific brand or model. This ensures that you buy the right type, which will not affect its efficiency.

d). Filtration Level

Most disposable furnace filters are rated according to the Minimum Efficiency Reporting Value (MERV) scale, which shows the efficiency of a filter. The higher the number, the finer it is and therefore the more particles it traps.

i). Disposable- this is the kind of filter you are likely to get for household use. They vary between MERV 6 and MERV 2, although MERV 8 is recommended as the minimum, and 10-11 are great for odor control.

ii). Commercial- Commercial furnaces have higher MERV ratings but are not suitable for use at home as most household systems don't generate a sufficient flow of air.

iii). Washable- not covered by minimum efficiency reporting value ad can be confusing. They also trap a certain percentage of particles, but they do not specify the sizes of those particles.

e). Ease of Installation

Different filters are installed differently. Some slide into the furnace housing. Others are located in the wall or even the ceiling near the HVAC system. You can easily tell the location of the filters by looking at your vents.

Ceiling filters have thumb tubs that you push outward to unlock the grate and pull it down to access the filter, while wall filters have a set-screw that holds the grating in place. Removing the screw opens the grate, giving you access to the filter.

Furnace Filter Ratings

There are three primary codes for furnace filter ratings that you may need to know before you purchase a furnace air filter: MERV, FPR, and MPR. Manufacturers test their efficiency after manufacturing an air filter furnace, which determines their ratings; it does not matter whether it has a MERV, MPR, or FPR rating. The higher the number, the better it is at trapping even the smallest particles.

a). FPR

Filter Performance Rating is a unified ranking system but does not have figures that make it easy to understand. Instead, it has a color-coded system that rates a filter's ability to filter certain particles and their quality. It also has a number scale ranging between four and 10.

b). MPR

MPR stands for Microparticle Performance Rating and is created by 3M. Although it is trusted, it is only used for 3M and Filtrete brand filters. A furnace filter with an MPR rating of 2800 is ideal for trapping smaller particles of one micron.

c). MERV

MERV, also Minimum Efficiency Reporting Value, is the industry standard and is the only one rated as a nationally regulated system. It was developed to identify a filter's ability to trap air pollutants. Minimum Efficiency Reporting Value has a scale of 1-20, with 20 being the best.

The major problem with MERV is that a rating above 13 can block airflow and cause backpressure in your system, leading to decreased efficiency. Therefore, you will only need to buy a high MERV-rated filter but only to what your furnace can accommodate.

Ian Mutuli

About the author

Ian Mutuli

Founder and Managing Editor of Archute. He is also a graduate architect from The University of Nairobi, Kenya.
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