Whole-Home Media● In stock

20×20×4.5Air Filter

Actual size: 19.5″ × 19.5″ × 4.13″
Fits any 20x20x4.5 slot or return grille. Order by the size printed on your old filter.

Honeywell 5-inch-nominal family

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Picked by HVAC techs

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Pack size (bigger packs save more)

20x20x4.5 · MERV 11 · 2-Pack$83.98$77.49

Or subscribe: $25.99/filter delivered, never think about it again

MERV 11 · 2-Pack

$77.49

Common questions about 20x20x4.5

What is the actual size of a 20x20x4.5 filter?+

The nominal size printed on the frame is 20x20x4.5, but the filter actually measures 19.5" × 19.5" × 4.13". 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 20x20x4.5?+

MERV 8 handles everyday dust. MERV 11 is our most popular, it captures pet dander and pollen. MERV 13 adds smoke, bacteria, and virus-carrier capture. When in doubt, call us, a real HVAC tech answers.

How often should I change a 20x20x4.5 filter?+

Deep-pleat media filters like this 4.5-inch typically last 6-12 months. Check it at each season change.