Honeywell FC100A1029: What Size Is It Really? (16x25x4 or 16x25x5?)
Quick answer
Honeywell lists the FC100A1029 at 16 × 24⅞ × 4⅜ inches. It's the MERV 11 filter for Honeywell's 16 × 25 F100/F200 media air cleaners, and FC200E1029 is the MERV 13 version. [S1]
- The label varies: a retailer lists it as nominal 16x25x4 [S3], while Filterbuy calls the cabinet a 16x25x5. [S4] All three sources agree it's about 4⅜ in deep.
- A standard 16x25x4 (about 3.63–3.75 in deep) won't fit this cabinet. Filterbuy says it leaves a gap that unfiltered air flows through. [S4]
- Honeywell recommends replacing the filter every six months and at least once a year, or when the pressure drop across it reaches 0.5 in. w.c. [S1]
Published dimensions for FC100A1029
The sources don't agree to the sixteenth of an inch, but all of them put the depth at 4⅜ inches.
Honeywell F100/F200 replacement filters
From Honeywell's replacement filter table. Every one is 4⅜ inches deep. [S1]
| Cabinet size | MERV 11 (F100) | MERV 13 (F200) | Filter size (in) |
|---|---|---|---|
| 16 x 25 | FC100A1029 | FC200E1029 | 16 × 24⅞ × 4⅜ |
| 16 x 20 | FC100A1003 | FC200E1003 | 16 × 19¾ × 4⅜ |
| 20 x 25 | FC100A1037 | FC200E1037 | 20 × 24⅞ × 4⅜ |
| 20 x 20 | FC100A1011 | FC200E1011 | 20 × 19¾ × 4⅜ |
| 12.5 x 20 | FC100A1052 | N/A | 20 × 12½ × 4⅜ |
MERV 11 vs MERV 13 (Honeywell's figures)
| F100 / FC100 (MERV 11) | F200 / FC200 (MERV 13) | |
|---|---|---|
| Static pressure drop at 500 FPM | 0.23 in. w.c. | 0.3 in. w.c. [S1] |
| E1 (0.3–1.0 µm) | 32% | 63% [S1] |
| E2 (1.0–3.0 µm) | 72% | 91% [S1] |
| E3 (3.0–10.0 µm) | 96% | 99% [S1] |
Conflict: AF Supply lists different efficiencies for FC100A1029 (E1 25%, E2 62%, E3 85%). [S3] The numbers above are from Honeywell's 2017 guide.
Why this filter confuses people
Honeywell's own replacement table lists the FC100A1029 by its 16 x 25 face, and the newer revision of the guide does the same. [S1] [S2] Retailers then add a third number: AF Supply says 4 [S3], and Filterbuy treats the cabinet as a 5-inch. [S4] The real depth, 4⅜ inches, sits between the two labels.
What to do: read the part number on your old filter or on the cabinet door. If it's an FC100A1029 or FC200E1029, buy one of those or a replacement listed at about 4⅜ inches deep. Don't go by the "x4" or "x5" on the label. [S1] [S4]
Where to buy
We don't link to specific sellers here yet. Search for the exact part number or size on this page at a retailer you trust, compare the listed actual dimensions, and check the current price. We don't list prices because they change daily.
FAQ
Is the FC100A1029 a 16x25x4 or a 16x25x5?
It's sold under both labels. A retailer lists it as nominal 16x25x4 [S3] and Filterbuy calls it a 16x25x5. [S4] Honeywell's guide gives the actual size as 16 × 24⅞ × 4⅜ inches. [S1]
What's the difference between FC100A1029 and FC200E1029?
They're the same size. FC100A1029 is Honeywell's MERV 11 filter for the F100, and FC200E1029 is the MERV 13 filter for the F200. [S1]
Which Honeywell air cleaners use the FC100A1029?
Honeywell's guide pairs it with the 16 × 25 F100 and F200 media air cleaners (F100F1625, F200F1625). [S1] AF Supply also lists the F25, F27, F35 and F150. [S3]
How often should I replace it?
Honeywell recommends every six months, before the heating and cooling seasons. Replace it at least once a year, or when the pressure drop across it reaches 0.5 in. w.c. [S1]
Can I use a regular 16x25x4 instead?
Filterbuy says no: a 3.63-inch filter in this cabinet leaves a gap that lets unfiltered air bypass the media. [S4]
What we could not verify
- Why the sources' face dimensions differ slightly (16 vs 15-15/16 vs 15.875 in wide). We report each one as published.
- Which efficiency numbers apply to current production. Honeywell's 2017 guide and AF Supply's listing disagree.
- Whether every older Honeywell cabinet AF Supply lists (F25, F27, F35, F150) takes this filter. Confirm your cabinet's model sticker or manual.
Sources
- [S1] Honeywell Media Air Cleaners Professional Installation Guide (68-0239EF-12, Rev. 10-17) — Honeywell International (PDF hosted by Build.com). Accessed 2026-10-24. Used for: Replacement table, filter dimensions, MERV/efficiency/pressure specs, replacement schedule.
- [S2] Honeywell Media Air Cleaners guide (68-0239EF-13) — Honeywell Home (PDF hosted by Baker Distributing). Accessed 2026-10-24. Used for: Newer revision confirming the same part numbers for each cabinet size.
- [S3] Honeywell FC100A1029/U MERV 11 Replacement Media Air Cleaning Filter — AF Supply. Accessed 2026-10-24. Used for: Nominal 16x25x4 label, actual size, compatible cleaners, alternate efficiency figures.
- [S4] 16x25x4 Air Filters — Filterbuy. Accessed 2026-10-24. Used for: Calls the cabinet a 16x25x5; warns that a 16x25x4 won't seal.
Last checked 2026-10-24. Spot an error? Tell us and we'll recheck it against the source.