Furnace · Best-of
Best 4-Inch and 5-Inch Furnace Filter (Deep Media)
The best deep-media filter pairs a true, honestly labeled MERV with low airflow restriction and yearly replacement - it outperforms a 1-inch filter at the same MERV on both airflow and running effort.
Deep-media filters (4-inch and 5-inch) are the technically correct way to run high MERV: far more surface area means strong filtration with little airflow restriction, and you replace them about once a year instead of quarterly. If your system has a media cabinet, this is the format to buy.
How we score: We surface 4-inch and 5-inch deep-media filters and rank by composite, which rewards honest MERV labeling and credits the low airflow restriction of deep media.
- 16.6Aprilaire 213 (4-inch media, MERV 13)
The Aprilaire 213 (4-inch media, MERV 13) is a 4-inch deep-media furnace filter rated MERV 13 on the standardized ANSI/ASHRAE 52.2 scale, which captures fine particles including smoke and many bacteria-size particles. It labels its true MERV with no proprietary scale. Its deep media keeps airflow restriction low even at this MERV. Replaced about 1 time a year, it runs roughly $69 per year.
- True MERV (ASHRAE 52.2): MERV 13
- Depth: 4 inch (deep media, low airflow restriction)
- Annual filter cost: $69/yr
- 26.6Aprilaire 413 (4-inch media, MERV 13)
The Aprilaire 413 (4-inch media, MERV 13) is a 4-inch deep-media furnace filter rated MERV 13 on the standardized ANSI/ASHRAE 52.2 scale, which captures fine particles including smoke and many bacteria-size particles. It labels its true MERV with no proprietary scale. Its deep media keeps airflow restriction low even at this MERV. Replaced about 1 time a year, it runs roughly $69 per year.
- True MERV (ASHRAE 52.2): MERV 13
- Depth: 4 inch (deep media, low airflow restriction)
- Annual filter cost: $69/yr
- 36.0Honeywell FC100A1037 (4-inch media, MERV 11)
The Honeywell FC100A1037 (4-inch media, MERV 11) is a 4-inch deep-media furnace filter rated MERV 11 on the standardized ANSI/ASHRAE 52.2 scale, which captures fine dust, pollen, and pet dander. It labels its true MERV with no proprietary scale. Its deep media keeps airflow restriction low even at this MERV. Replaced about 1 time a year, it runs roughly $65 per year.
- True MERV (ASHRAE 52.2): MERV 11
- Depth: 4 inch (deep media, low airflow restriction)
- Annual filter cost: $65/yr
- 45.4Lennox Healthy Climate X6673 (5-inch media, MERV 11)
The Lennox Healthy Climate X6673 (5-inch media, MERV 11) is a 5-inch deep-media furnace filter rated MERV 11 on the standardized ANSI/ASHRAE 52.2 scale, which captures fine dust, pollen, and pet dander. It labels its true MERV with no proprietary scale. Its deep media keeps airflow restriction low even at this MERV. Replaced about 1 time a year, it runs roughly $72 per year.
- True MERV (ASHRAE 52.2): MERV 11
- Depth: 5 inch (deep media, low airflow restriction)
- Annual filter cost: $72/yr
FAQ
- Do I need a special cabinet for 4-inch filters?
- Yes. Deep-media filters fit a media-filter cabinet (Aprilaire, Honeywell, Lennox, and similar) installed at the air handler, not the standard 1-inch return-grille slot. Check what your system has.
- Why is deep media better at high MERV?
- Surface area. A 4-inch filter has far more pleated media than a 1-inch panel, so it can hit MERV 13 while restricting airflow far less and lasting about a year.