Filters

Written by Ralph Desmornes on

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As the name implies, furnace filters clean the air that cycles through your furnace. The purpose of a filter is actually to protect the blower fan from dust, dirt and debris, but furnace filters also ensure that cleaner air circulates throughout your home. If you also have an air conditioner, the two systems share a filter, which may be interchangeably referred to as a furnace filter or an air conditioner filter. Selecting the best filter to meet your needs can be confusing, but this guide can help you compare the top brands and models of furnace filters.

How do you find the best furnace filters?

To find the best furnace filters, we looked at a variety of criteria including features, cost and reliability. We broke down the criteria to make side-by-side comparisons of different brands and models. Here’s what we looked for:

Features

Cost

  • Unit price
  • Availability

Reliability

  • Customer reviews
  • Advertised lifespan

Note that you should look for a few specific things when buying a furnace filter. The most important is the filter’s size. It must precisely fit in its designated location — “close enough” isn’t sufficient. Make sure you know exactly what size filter you need.

Filters may or may not be pleated. Pleated filters are generally considered superior because there is more surface area to catch contaminants as well as the opportunity for pores to be smaller without restricting airflow.

The MERV rating determines what size particles the filter can trap, with higher ratings indicating the ability to catch smaller particles. MERV ratings vary from 1 to 16. Ratings of 4 or below are generally the least expensive, but they allow the most contaminants to remain in the air. Ratings of 5 to 8 are typically sufficient for homes with healthy people and no pets.

A MERV rating of 9 to 12 is typically recommended for the average home. If you are a pet owner or someone in your family has allergies or asthma, it is especially important to choose a filter with a MERV rating of 9 or above.

MERV ratings above 12 indicate that the filter can trap extremely small particles. These filters are pricey and generally only worthwhile for “clean room” applications and homes with people suffering from more severe respiratory ailments. Be sure to check with your furnace manufacturer to see if there is a maximum recommended MERV rating. These filters tend to restrict airflow and are not appropriate for all furnaces.

Best furnace filters

Best Tech: Filtrete 2500 Smart Filter

Long known as a technological leader in the filtration market, Filtrete now offers a line of smart filters that monitor your usage and let you know when they need to be changed. The Filtrete Smart App also stores your filter type and size information, monitors air quality, gives suggestions for improvement and makes it easy to order replacement filters.

We especially like the 2500 model, designed for premium protection against allergens and ultrafine particles. If you’re going through the trouble of connecting to a smart filter, it might as well be a really good one.

Features

  • Available in a variety of standard sizes
  • MERV rating 12
  • Smart technology, Bluetooth connectivity, compatible with both Android and iPhone

Cost

  • $29.98 at Lowe’s (may vary depending on size)
  • Readily available at a variety of big box stores and online

Reliability

  • 4.5 stars across a variety of consumer reviews
  • Average lifespan of three months, depending on usage

Best for Budgets: Aerostar MERV 8

Aerostar is a reliable manufacturer of filtration products. For budget-minded households with no respiratory issues, the Aerostar MERV 8 is an excellent midrange choice.

Features

  • A variety of standard sizes are available
  • MERV rating 8
  • Electrostatic pleated filters to trap dust, pollen and other irritants

Cost

  • $29.63 for a pack of 6 filters at Walmart (may vary depending on size)
  • Easy to find at big box stores and online

Reliability

  • 4.5 stars across numerous customer review sites
  • Average lifespan of one to three months, depending on season and usage

Best Odor Removal: Filtrete 1200 Odor Reduction Filter

If you live with pets, cook frequently or battle mildew, you know how easily odors can settle into your home. If removing these smells is at the top of your priority list, the Filtrete 1200 Odor Reduction filter is hard to beat. These filters are 25 times more effective at odor removal than other national brands, thanks to an added layer of activated carbon, a powerful purifier with the ability to bond with and trap a variety of contaminants.

Features

  • Available in nearly every standard size
  • MERV rating 11
  • Activated carbon layer, filter change reminders via Filtrete Smart App or email

Cost

  • $14.99 at Target (may vary depending on size)
  • Easy to find online and at a variety of big box stores

Reliability

  • 4.8 stars across numerous customer review sites
  • Average lifespan of three months, depending on usage

Honeywell Micro Defense Standard Efficiency

The Honeywell Micro Defense Standard Efficiency filter has a 15% microparticle capture rating, outperforming any other filter in its class.

Features

Cost

  • $7.99 at HoneywellStore.com (may vary depending on size)
  • Readily available at big box stores as well as online

Reliability

  • 4.75 stars across a range of customer review sites
  • Average lifespan of three months, depending on usage

Nordic Pure MERV 10

The Nordic Pure MERV 10 is an excellent choice for households seeking a balance between efficiency and price.

Features

  • A wide range of standard sizes are available
  • MERV rating 10
  • Electrostatic, hypoallergenic and antimicrobial

Cost

  • $31.08 for a 3-pack at Amazon.com (may vary depending on size)
  • Sold online and at big box stores

Reliability

  • 4.5 stars across numerous consumer review sites
  • Average lifespan of three months, depending on usage

Furnace filters have the primary job of keeping dust and debris from the blower fan, but they also help clean the air that circulates throughout your home. When choosing a filter, be sure to select the MERV rating and features that best fit your household’s needs.