4-Inch Pleated● Shipping included

20×20×4Air Filter

Actual size: 19.375″ × 19.375″ × 3.75″
Fits any 20x20x4 slot or return grille. Order by the size printed on your old filter.

Standard 4-inch pleated filter for 4-inch filter racks. Honeywell, AprilAire, Carrier and Lennox media cabinets take their own filter sizes, so check the actual size printed on your old filter first.

Case of 12
Shipping included
Picked by HVAC techs

Choose your protection level

20x20x4 · MERV 11

$256.99per case of 12, shipping included

About $21.42 a filter. Kentucky orders add 6% sales tax.

1 case, 12 filters1

Want a new case every year? A yearly subscription is available at checkout.

MERV 11 · Case of 12

$256.99

Common questions about 20x20x4

What is the actual size of a 20x20x4 filter?+

The nominal size printed on the frame is 20x20x4, but the filter actually measures 19.375" × 19.375" × 3.75". That undercut is intentional: it slides into your filter track without binding. Order by the nominal size printed on your old filter.

Which MERV rating should I pick for a 20x20x4?+

MERV 8 handles everyday dust. MERV 11 is our most popular. It captures pet dander and pollen. MERV 13 adds smoke and the finest everyday particles. When in doubt, call us. A real HVAC tech answers. Compare MERV 8, 11 and 13.

How often should I change a 20x20x4 filter?+

Deep-pleat media filters like this 4-inch typically last 6-12 months. Check it at each season change. See the schedule by household type.