20×25×4Air Filter
Fits any 20x25x4 slot or return grille. Order by the size printed on your old filter.Also sold as 25x20x4.
- Case of 12
- Shipping included
- Picked by HVAC techs
About $20.83 a filter. Kentucky orders add 6% sales tax.
Want a new case every year? A yearly subscription is available at checkout.
Common questions about 20x25x4
What is the actual size of a 20x25x4 filter?+
The nominal size printed on the frame is 20x25x4, but the filter actually measures 19.375" × 24.375" × 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 20x25x4?+
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 20x25x4 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.
Is a 25x20x4 the same as a 20x25x4?+
Yes, 20x25x4 and 25x20x4 are the same filter; the dimensions are just written in a different order. This filter fits both.