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Advanced Thermal Concepts LLC
All filters/Sizes/20x20x1
Top Seller1-Inch Pleated● In stock

20×20×1Air Filter

Actual size: 19.5″ × 19.5″ × 0.75
Fits any 20x20x1 slot or return grille. Order by the size printed on your old filter.
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Choose your protection level
Pack size (bigger packs save more)
20x20x1 · MERV 11 · 3-Pack$44.97$28.99
Or subscribe: $9.49/filter delivered, never think about it again
MERV 11 · 3-Pack
$28.99

Common questions about 20x20x1

What is the actual size of a 20x20x1 filter?+

The nominal size printed on the frame is 20x20x1, but the filter actually measures 19.5" × 19.5" × 0.75". 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 20x20x1?+

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, and it's fine in modern systems (post-1995 blowers). When in doubt, call us, a real HVAC tech answers.

How often should I change a 20x20x1 filter?+

Every 30-90 days. Monthly if you have pets or allergies; every 2-3 months otherwise. Our subscription handles the schedule for you.

Nearby sizes