4 Inch Furnace Filters
4-inch furnace filters for media cabinets and deep filter racks. Shop Honeywell FC100A, FC200E and FR8000 filters, Aprilaire 210, 213, 410 and 413 media, Lennox PureAir filters, FG Aerostar and PureFilters pleated 3-packs. The most common sizes are 16x25x4, 20x25x4 and 20x20x4. Search by the part number on your current filter.
For 5-inch cabinets, see 5 inch furnace filters; for slimmer racks, see 2 inch furnace filters. Every size is in furnace filters.
4-inch filter guide: part numbers, sizes and fit ▾
Find your filter by part number
Most 4-inch filters fit a media cabinet made by Honeywell, Aprilaire, Lennox or another brand, and each cabinet is built for its own filter. The part number on the old filter or the cabinet label is the safest match. Two filters with the same nominal size can differ in actual dimensions from one brand to another, so do not rely on size alone. Our filter size guide explains nominal vs actual size.
Popular 4-inch filters
| Brand | Part # | Size | MERV |
|---|---|---|---|
| Honeywell | FC100A1029 | 16x25x4 | 11 |
| Honeywell | FC200E1029 | 16x25x4 | 13 |
| Honeywell | FC100A1037 | 20x25x4 | 11 |
| Honeywell | FC200E1037 | 20x25x4 | 13 |
| Honeywell | FC100A1011 | 20x20x4 | 11 |
| Honeywell | FR8000A2020 | 20x20x4 | 15 |
| Aprilaire | 410 | 16x27x4 | 11 |
| Aprilaire | 413 | 16x27x4 | 13 |
| Aprilaire | 210 | 20x26x4 | 11 |
| Aprilaire | 213 | 20x26x4 | 13 |
| Aprilaire | 313 | 20x20x4 | 13 |
| Lennox | X6664 (PureAir PCO-12C) | 17x26x4 | 11 |
| Lennox | X6667 (PureAir PCO-20C) | 21x26x4 | 11 |
MERV rating and replacement
Replace like for like with the MERV rating your cabinet was designed for; higher ratings can restrict airflow in some systems. Our MERV rating guide compares each level. Thick media filters hold more dust than 1-inch filters and typically last about 6 to 12 months, depending on the filter and how much the system runs. Check yours every few months and follow the cabinet maker's schedule.
