20×20×1 air filter
Fits any system that takes a 20×20×1 filter. Actual size 19.75 × 19.75 × 0.75 inches, made to within 1/16 inch and measured before it ships. Made in the USA. Free shipping; you see your arrival date before you pay.
Grades and prices
| Grade | What it catches | Price per filter |
|---|---|---|
| Everyday (MERV 8) | Dust, lint and pollen. The right pick for most homes. | 4-pack $8.31 each, 6-pack $6.35 each, 12-pack $5.97 each |
| Allergy (MERV 11) | Adds pet dander and mold spores. For pets and allergy season. | 4-pack $11.64 each, 6-pack $8.88 each, 12-pack $8.35 each |
| Allergy + Smoke (MERV 13) | Adds smoke, smog and fine particles. For wildfire season and asthma. | 4-pack $12.89 each, 6-pack $9.84 each, 12-pack $9.25 each |
Subscribe and save 10%. Choose When you need it, timed to your local weather, air quality and household and billed per box, or Every few months, a box every 3, 6 or 12 months. Skip, change or cancel anytime.
Dimensions
- On the label
- 20 × 20 × 1 in
508 × 508 × 25 mm - Actual filter
- 19.75 × 19.75 × 0.75 in
502 × 502 × 19 mm - Face area
- 2.78 sq ft
0.26 m²
Where this size goes
In the 1,116 furnace and air handler models we've sized from manufacturer spec sheets:
- 179 air handlers take a 20×20×1 in the unit or its filter stand (American Standard, Carrier, Goodman, Lennox, Mitsubishi and others).
Examples: American Standard 2TEE3F31, Carrier FE5BNBC36L00, Goodman AMVT36CP14, Lennox CBA38MV-018. Look up your model.
How often to change it
| Household | Everyday (MERV 8) | Allergy (MERV 11) | Allergy + Smoke (MERV 13) |
|---|---|---|---|
| A typical home | 3 months | 3 months | 2.5 months |
| With pets | 2 months | 2 months | 7 weeks |
| Pets and allergies, or smoke season | 6 weeks | 6 weeks | 5 weeks |
Heating and cooling season, pollen and wildfire smoke shorten these; mild spring and fall weeks stretch them. More on timing.
How long a pack lasts
| Pack | Typical home | With pets | Everyday, a month |
|---|---|---|---|
| 4-pack | 11 months | 7 months | $3.02 |
| 6-pack | 17 months | 11 months | $2.24 |
| 12-pack | 33 months | 22 months | $2.17 |
On a subscription we send each box when your home needs it, so you never store more than you use.
Questions about 20×20×1 filters
Is 20×20×1 the real size?
Not quite, and that's normal. 20×20×1 is the size on the label. The filter itself measures 19.75 × 19.75 × 0.75 in (502 × 502 × 19 mm), a little smaller so it slides into the slot. We make ours to within 1/16 inch of that.
How much does a 20×20×1 filter cost?
In a 6-pack, Everyday (MERV 8) is $6.35, Allergy (MERV 11) is $8.88, Allergy + Smoke (MERV 13) is $9.84 per filter. A 12-pack costs a little less per filter, and subscribing saves another 10%. Free shipping in the US.
How often should I change a 20×20×1 filter?
About every 3 months in a typical home with Everyday or Allergy, and every 2.5 months with Allergy + Smoke. With pets, closer to every 2 months. Heating and cooling season, pollen and smoke fill it faster, so "When you need it" times each swap to your home's weather and household instead of the calendar.
Can I use an 18×20×1 instead?
No. Even an inch matters. A smaller filter leaves a gap that lets dusty air slip around it, and a bigger one won't slide in. Order the exact size printed on your old filter's edge. If it's a size no store carries, we make any custom size, priced like the next standard size up.
Will a 20×20×2 fit where my 20×20×1 goes?
Only if the slot is 2 inches deep. A 2" filter needs a rack or grille built 2 inches deep, so it won't fit a 1" slot. If your slot is 1", stay with 20×20×1.
What if it doesn't fit?
Tell us within 30 days and we'll send a new one free, and you keep the first. That's our fit guarantee.