6 Inch Furnace Filters
6-inch furnace filters for media air cleaner cabinets, led by Electro Air Five Seasons replacements, Aprilaire Space-Gard 201, 401 and 501, Lennox PMAC and GeneralAire media. Common sizes are 16x25x6 and 20x25x6, from MERV 10 to MERV 16. Order by the part number on your current filter rather than by size alone.
If your cabinet takes a thinner filter, see 5 inch furnace filters, or browse every size in furnace filters.
6-inch filter guide: part numbers and sizes ▾
Why the part number matters
Six-inch filters are built for a specific cabinet. Brands write sizes differently (Aprilaire and Lennox list 25x20x6 where others say 20x25x6), and actual dimensions vary, so match the part number on your old filter or cabinet label. Our filter size guide explains nominal vs actual size.
Popular 6-inch filters
| Brand | Part # | Size | MERV |
|---|---|---|---|
| Electro Air Five Seasons | M1-1056 | 16x25x6 | 11 |
| Electro Air Five Seasons | M8-1056 | 20x25x6 | 11 |
| Electro Air Five Seasons | M2-1056 | 20x20x6 | 11 |
| Electro Air Five Seasons | G1-1056 | 16x25x6 | 14 |
| Electro Air Five Seasons | G8-1056 | 20x25x6 | 14 |
| Aprilaire Space-Gard | 201 | 25x20x6 | 10 |
| Aprilaire Space-Gard | 401 | 16x27x6 | 10 |
| Lennox | X0444 (PMAC-12C) | 28x17x6 | 10 |
| Lennox | X5425 (PMAC-12C) | 28x17x6 | 16 |
| Lennox | X0445 (PMAC-20C) | 25x20x6 | 10 |
| GeneralAire / Reservepro | 13415 | 16x25x6 | 11 |
| GeneralAire / Reservepro | 12758 | 20x25x6 | 11 |
How often to replace
Deep media filters like these typically last about 6 to 12 months. Follow your cabinet maker's schedule and check the filter's condition; see our filter change guide.
