When you're shopping for air filtration indoor air quality, the practical question is usually not which brand-it's which filter size your system takes and how many replacements you want on hand. Both of these are genuine Honeywell media filters with a MERV 11 rating, but they're made for different filter openings. One comes as a two-pack, the other as a five-pack, and the right choice depends on your cabinet dimensions and your replacement schedule.
Quick verdict
Pick the two-pack if you need the larger filter opening and don't want to make as large a first purchase. Pick the five-pack if you need the smaller filter opening and want more replacements in a single order. Between the two, the deciding factors are which opening your HVAC system uses and whether you'd rather buy fewer filters at a time or stock a longer supply. The five-pack comes with a higher listed price, while the two-pack is the lower listed price of the pair.
Comparison at a glance
| Feature | Genuine Honeywell FC100A1037 20x25x4 Merv 11 -2 Pack | 5 PACK - Genuine Honeywell FC100A1003 16x20x4 Media HVAC Air Filter MERV 11 |
|---|---|---|
| Listed price | USD 52.99 | USD 114.99 |
| Price bar | ||
| Nominal size | 20 x 25 x 4 | 16 x 20 x 4 |
| Quantity | 2 filters | 5 filters |
| Filter life | 6-8 months per filter | 6 months per filter |
| Filter media | Pleated fabric, cardboard frame | Synthetic media |
| Color | Gray | White |
Where each product wins
- FC100A1037 wins if your system uses the larger opening in this comparison. It's the smaller first purchase, includes two filters, and uses a pleated fabric media with a cardboard frame.
- FC100A1003 wins if your system uses the smaller opening. It includes five filters, works out to a lower cost per filter at the listed prices, and uses synthetic media. It's also listed as a replacement for Honeywell F100F1004, F100B1008, F150E1000, F100F2028, and F25/F35/F100/F150 series air cleaners.
Product notes
Genuine Honeywell FC100A1037 HVAC Replacement Air Filter 20x25x4 Merv 11 -2 Pack
This Honeywell two-pack is for the larger filter opening. The purchase includes both filters, so you have one filter in use and one ready to swap in. The pleated fabric media and cardboard frame are the construction details that define this pack, and the filter is available in gray. For someone who wants to keep the first purchase smaller and confirm the fit before committing to a longer supply, this two-pack is the practical place to start. It carries the same MERV 11 rating as the other filter, but the real difference here is inventory: after the first changeout, you have one spare left, so a full year of scheduled changes may mean another order sooner than it would with a five-pack.
5 PACK - Genuine Honeywell FC100A1003 16x20x4 Media HVAC Air Filter MERV 11
This Honeywell five-pack is built for the smaller filter opening and gives you the full pack in one purchase. It's listed as a replacement for Honeywell air cleaner models including the F100F1004, F100B1008, F150E1000, and F100F2028. The MERV 11 media is synthetic, and the model's compatibility list covers several Honeywell F-series air cleaners. The main advantage is quantity: more spares stocked and fewer orders over time. The limitation is the larger first purchase and the storage space for five filters. If your system doesn't take this size, the five-pack won't help you, so the size check needs to come first and the purchase decision follows from that fit.
Final choice by use case
- For a 20x25x4 system: Choose the Genuine Honeywell FC100A1037 HVAC Replacement Air Filter 20x25x4 Merv 11 -2 Pack.
- For a 16x20x4 system: Choose the 5 PACK - Genuine Honeywell FC100A1003 16x20x4 Media HVAC Air Filter MERV 11.
Confirm the filter opening in your system before ordering, then match it to the filter that corresponds to that size. The two-pack keeps the first purchase smaller, while the five-pack gives you more replacements in one order.
