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21.5x23.25x1 Air Filters

MERV 8 (Standard)
MERV 8
MERV 8 Badge
3 Month Badge

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2. Select Filter Quantity

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21.5x23.25x1 Air Filter Description

Actual Size: 21.5x23.25x1"
Model: AFB21.5x23.25x1M8A
Available In MERV Rating: 6 , 8 , 11 , 13
Made in the USA
Ships in 24 hours

MERV Rating Information

MERV 6 (Basic)

Actual: 21.5x23.25x1"
Model: AFB21.5x23.25x1M6A
MERV 6 Badge
3 Month Badge
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6 for 23.91 each

5% discount

•Pollen•Dust Mites•Mold•Basic Residential Use

MERV 8 (Standard)

Actual: 21.5x23.25x1"
Model: AFB21.5x23.25x1M8A
MERV 8 Badge
3 Month Badge
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6 for 24.01 each

5% discount

•Pollen•Dust Mites•Mold•Larger dust particles, like pudding mix•Standard residential / commercial use

MERV 11 (Superior)

Actual: 21.5x23.25x1"
Model: AFB21.5x23.25x1M11A
MERV 11 Badge
3 Month Badge
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6 for 27.19 each

5% discount

•Pollen•Dust Mites•Mold•Auto Emissions / Large Particles like Milled Flower•Superior Commercial and Residential

MERV 13 (Best)

Actual: 21.5x23.25x1"
Model: AFB21.5x23.25x1M13A
MERV 13 Badge
3 Month Badge
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6 for 30.39 each

5% discount

•Pollen•Dust Mites•Mold•All Bacteria•Proplet Nuceli (sneeze)•Smoking Lounges•Best of breed, hospital grade filter

Benefits of the FilterBuy 21.5x23.25x1 Filter

• LONG-LASTING

FilterBuy filters are designed to last up to 90 days, 3 times longer than fiberglass filters. If you have pets, kids, or allergy sufferers in your home or business, replace your filters more often to maintain superior indoor air quality and keep your energy costs low.

• MADE IN THE USA

All air filters are manufactured by FilterBuy in the USA using 100% American made components. By purchasing directly from the manufacturer, you’re saving big on a premium product.

• HIGH QUALITY

21.5x23.25x1 pleated air filters are at least 20 times more efficient than fiberglass filters. Filter frames are made of beverage board, which stays strong through humidity and temperatures up to 200° F. Synthetic media provides significantly higher particulate efficiency than standard cotton media.

Specifications
Nominal size
21.5x23.25x1
Actual size
21.5x23.25x1"
Made in
USA
Designed to last
90 days
Pleats per foot
14
Frame made of
Beverage board
Pleats made of
Synthetic media
Certification
Underwriters Laboratories U.L Class 2

Is it Time to Change Your Filter?

Generally, we recommend you replace your air filters every 90 days. Find out below if you should change your filters more often.

If someone in your home has asthma and/or allergies... ...change your filter every 6 weeks to ensure indoor air quality is at its best.

If you have pets... ...change your filter every 2 months to avoid shedding and odor buildup.

If you have young children... ...change your filter every 2-3 months, as having clean air is even more important with children in your home.

If you want to know more about when to replace your air filter, click here.

MERV 6
  • The 21.5x23.25x1 MERV 6 filter offers basic filtration while removing most particulates from the air.
  • Traps and blocks 85% of air particles in your space, including pollen, dust mites, and mold.
  • Ideal for use in basic homes.
MERV 8
  • The 21.5x23.25x1 MERV 8 filter is our most popular rating, as it filters well in most spaces.
  • Traps and blocks 90% of air particles in your space, including pollen, dust mites, mold, and large particles like pudding mix.
  • Ideal for basic and standard homes and businesses.
MERV 11
  • The 21.5x23.25x1 MERV 11 filter blocks almost all bacteria from the air while keeping proper air flow and minimizing system backpressure.
  • Traps and blocks 95% of air particles in your space, including pet dander, lint, dust, pollen, debris, mold spores, smoke, and smog.
  • Ideal for standard and superior homes and businesses.
MERV 13
  • The 21.5x23.25x1 MERV 13 filter is our best-of-breed filter, providing maximum filtration while elevating the performance of your HVAC system.
  • Traps and blocks 98% of air particles in your space, including pet dander, lint, dust, pollen, debris, mold spores, smoke, smog, and bacteria–even particles that carry viruses.
  • Ideal for superior homes and businesses and smoking lounges.

For more information about MERV ratings, click here.

21.5x23.25x1 Air Filter Reviews

Rolling
x

Build a Custom Size

Simply measure the length and width of your filter with a tape measure and choose the closest size (to 1/8”) in the drop down menu. 1/8” tolerance is standard and should not cause a problem in any standard filter application.

Please note that the ‘actual’ filter size, ie the size that your tape measure shows, should be used when creating a filter with this tool, not a nominal filter size. Note that the depths of each filter are standard, as shown to the right.

Simply measure the length and width of your filter with a tape measure and choose the closest size (to 1/8”) in the drop down menu. Please note that the filter depth is standard.