A 20x25x5 air filter is the standard size for whole-home media filter cabinets installed on Honeywell, Aprilaire, Lennox, and other major HVAC brands. The 5 inch depth holds 8 to 12 times more filter media than a 1 inch return filter, which means lower pressure drop, better dust capture, and change intervals measured in months instead of weeks. After comparing 12 of the most common replacement filters across MERV rating, airflow resistance, and actual loaded life, these five covered the practical residential range.
Quick comparison
| Pick | MERV | Brand cabinet fit | Best for |
|---|---|---|---|
| Aprilaire 213 | 13 | Aprilaire 1210/2210/4200 | Best overall |
| Honeywell FC100A1037 | 11 | Honeywell F100/F200 | Best for Honeywell cabinets |
| Lennox X6673 | 16 | Lennox HCC16-28 | Best for high-MERV systems |
| Filterbuy MERV 11 20x25x5 | 11 | Multi-brand | Best value |
| Aprilaire 210 | 11 | Aprilaire 1210/2210/4200 | Best for older Aprilaire cabinets |
Aprilaire 213 - Best Overall
The Aprilaire 213 is the MERV 13 replacement for Aprilaire 1210, 2210, 3210, and 4200 media cabinets. The pleated synthetic media is deep-pleat construction with roughly 75 pleats across the 20 inch width, giving large surface area for capture and low pressure drop. MERV 13 captures dust mite debris, mold spores, pet dander, and most pollen, plus a portion of smoke and bacteria carriers.
Loaded life runs 9 to 12 months in a typical 3-bedroom home with one pet, 6 to 8 months with multiple pets or active allergies. The cardboard frame is rigid enough to slide in and out cleanly without bowing, which matters because a flexed filter lets unfiltered air bypass around the edges.
Around $35 to $45 per filter, $80 to $110 for a 3-pack. The right pick for most homes running an Aprilaire media cabinet, balancing capture quality, airflow, and replacement interval. Confirm your cabinet model before ordering.
Honeywell FC100A1037 - Best for Honeywell Cabinets
The Honeywell FC100A1037 is the MERV 11 replacement for Honeywell F100, F150, and F200 media cabinets. Actual dimensions are 20x25x4.38 inches, which fits the Honeywell cabinet correctly but will not seal properly in a true 5 inch slot from another brand. MERV 11 captures dust, pollen, and most pet dander, slightly less than MERV 13 on the finer particles.
The pleated electrostatic media holds dust capture rating across the loaded life without significant pressure drop increase. Replacement is straightforward; the filter slides in the direction marked by an arrow on the frame.
Around $25 to $35 per filter, $60 to $90 for a 3-pack. The right pick for Honeywell cabinet owners who want a direct-fit MERV 11 without paying for MERV 13 capture. Most homes do not need the MERV 13 step up.
Lennox X6673 - Best for High-MERV Systems
The Lennox X6673 is a MERV 16 filter for Lennox HCC16-28 healthy climate cabinets and compatible systems. MERV 16 captures particles down to 0.3 microns at 95 percent efficiency, near HEPA performance, including most virus carriers and smoke. The trade-off is higher pressure drop; the blower motor on the HVAC system must be rated for the static pressure load.
This is not a drop-in replacement for cabinets specced for MERV 11 or MERV 13. Running MERV 16 on a system not designed for it causes airflow reduction, longer run times, and potential coil icing on AC. Verify with the HVAC installer before swapping up to MERV 16.
Around $60 to $85 per filter. The right pick for homes with high-allergy occupants, recent smoke exposure, or medical-grade air requirements, on systems already specced for MERV 16 operation.
Filterbuy MERV 11 20x25x5 - Best Value
Filterbuy is an aftermarket brand that makes 20x25x5 MERV 11 replacement filters cross-compatible with Honeywell, Aprilaire, and several smaller cabinet brands. The construction is pleated synthetic media with a cardboard frame, similar to the major brands at a meaningfully lower price. Confirm the actual dimensions match the cabinet before ordering; Filterbuy sells different actual depths under the same nominal 20x25x5 listing.
Capture and pressure drop are in line with major-brand MERV 11 in controlled comparison. Loaded life is similar at 8 to 10 months for a typical home. Quality control on the frame and pleat consistency is acceptable but not as tight as Aprilaire; about 1 in 20 filters arrive with minor frame damage from shipping.
Around $20 to $28 per filter, $50 to $70 for a 3-pack. The right pick for buyers who change filters on schedule and want MERV 11 capture at the lowest credible price.
Aprilaire 210 - Best for Older Aprilaire Cabinets
The Aprilaire 210 is the MERV 11 version of the same form factor as the 213. For Aprilaire 1210, 2210, 3210, and 4200 cabinets where the homeowner wants slightly longer life and lower pressure drop than the 213, the 210 is the right choice. MERV 11 capture is enough for most homes without active allergy or asthma issues.
Loaded life runs 10 to 14 months in lower-occupancy homes. Construction matches the 213 with the same deep-pleat synthetic media and rigid cardboard frame.
Around $28 to $38 per filter. The right pick for Aprilaire cabinet owners who want maximum interval and acceptable capture, not maximum capture.
How to choose a 20x25x5 air filter
Match the cabinet brand and model
The nominal 20x25x5 size is a category, not a precise fit. Actual depth varies from 4.38 inches (Honeywell) to 6 inches (Aprilaire 201). Pulling the existing filter and reading the model number printed on the frame is the simplest way to confirm fit. The cabinet door usually has a sticker listing compatible filter part numbers.
Pick MERV rating to the home
MERV 11 is the default for most homes. MERV 13 makes sense for homes with allergy or asthma issues, indoor pets, or active wildfire smoke seasons. MERV 16 only makes sense on systems specifically designed for it, because the airflow restriction can damage standard HVAC.
Buy 3-packs for the discount
Filters are not perishable for 2 to 3 years in storage. Buying a 3-pack at the start of the year cuts cost 20 to 30 percent compared to single-filter orders and removes the risk of running past the change date because you forgot to order.
Set a calendar reminder for changes
The most common failure mode for 20x25x5 filters is owners forgetting to change them. A 14-month-old filter looks the same as a 6-month-old filter from the outside. Set a calendar reminder for the planned change date and write the install date on the frame in marker.
For more on HVAC maintenance, see our HVAC media cabinet sizing comparison and our air purifier guide for allergies. Our testing methodology explains how we compare filters across airflow and capture.
A 20x25x5 air filter is one of the highest-leverage maintenance items in a home. The Aprilaire 213 is the default pick for most Aprilaire cabinets. The other four picks cover Honeywell-specific fit, high-MERV needs, value, and longer-interval lower-MERV use.
Frequently asked questions
What MERV rating should I pick for a 20x25x5 filter?+
MERV 11 is the sweet spot for most homes with standard residential HVAC. It captures pollen, dust mite debris, and most pet dander without restricting airflow. MERV 13 captures finer particles including some bacteria carriers and smoke, but requires the system to handle a small pressure drop increase. MERV 16 captures the finest particles but should only run on systems specifically rated for high-MERV media. Check the blower motor spec before going above MERV 13.
How often should I change a 20x25x5 filter?+
Every 6 to 12 months for most homes, which is the main reason this filter size exists. The 5 inch depth holds far more media than a 1 inch filter, so it loads slowly and resists pressure drop. Households with pets or active allergies should aim for 6 months. Lower-occupancy homes without pets can stretch to 12 months. Inspect at month 4, then again at month 8 to calibrate your interval.
Will a thicker filter damage my HVAC?+
No, a 5 inch media filter actually reduces strain compared to a clogged 1 inch filter, because the larger surface area lowers pressure drop. The risk only appears when you swap a 1 inch slot for a 5 inch media cabinet without verifying the return duct geometry. If your system was originally specced with a media cabinet, dropping in a replacement 20x25x5 filter is correct. Confirm fit measurements before ordering.
What is the difference between Honeywell, Aprilaire, and Lennox 20x25x5 filters?+
The nominal size is identical at 20x25x5 inches, but the actual dimensions differ by brand. Honeywell FC100A1037 is 20x25x4.38 inches actual. Aprilaire 201 is 20x25x6 inches actual. Lennox X6673 is 20x25x5 inches actual. Filters are not cross-compatible between cabinet brands without verifying the exact cabinet model. Look at the bracket on your existing filter or the model number on the cabinet door before ordering.
Are washable 20x25x5 filters worth it?+
Not for most homes. Washable filters in this size run 60 to 120 dollars, capture less than MERV 8 equivalent, and require monthly washing for the rated airflow. The labor and lower capture rate make disposable MERV 11 or MERV 13 media a better choice for almost every household. Washable can make sense only for buyers who replace filters extremely infrequently and accept the lower capture performance for the savings.
Morgan Davis
Morgan Davis writes for The Tested Hub.