16x25x5 Air Filter Buyer Guide: Fit, MERV, and Brands

A 16x25x5 air filter sits inside a metal cabinet bolted to your furnace or air handler, and getting the wrong one means it either won't slide in or leaves gaps that let unfiltered air bypass the media entirely. That's not a minor annoyance. Unfiltered air accelerates coil fouling, drives up energy costs, and pushes dust straight back into your living space.

This guide covers the exact dimensions you need, which HVAC brands and cabinets use this size, how to pick the right MERV rating for your household, and when to swap in a fresh filter. If you've been staring at filter listings wondering whether a 16x25x4 is close enough — or whether the Honeywell, Lennox, Carrier, and Skuttle versions are interchangeable — you'll find those answers here. For the full overview of 5-inch media filters across every size and cabinet brand, start with our whole house air filter guide.

16x25x5 Air Filter Actual Size: What Actually Fits Your Cabinet

The numbers printed on a 16x25x5 furnace filter are nominal dimensions — a rounded label the industry uses for convenience. The actual filter you pull out of the box measures differently, and for "16x25x5" that actual size isn't a single number. It falls into one of four distinct depth classes, and they are not interchangeable. Order the wrong class and the cabinet door won't close, or the filter rattles loose and lets air bypass it.

The Four Actual-Size Classes of "16x25x5"

All four filters below are sold as "16x25x5," but their real dimensions differ by nearly a full inch in depth and more than an inch in width. Match your cabinet to the correct row before you buy.

Actual depth class	Actual size (W × H × D)	Cabinets & brands that use it
4⅜" deep	15¾ × 24¾ × 4⅜ (Lennox X6670); 15⅞ × 24⅞ × 4⅜ (Lennox X6672 MERV 16); Carrier box/EZ Flex 15¾ × 24¾ × 4-5/16	Lennox Healthy Climate HCC16-28 (X6670, X6672, X8309); Honeywell F-series (F25, F35, F50, F100, F150, F200); Carrier/Bryant cabinets EZXCAB016, MACA016, MPKA016, FILCAB016 — box FILXXCAR0016 (MERV 8) / FILXXCAR0116 (MERV 11) = EZ Flex EXPXXFIL0016 / EXPXXUNV0016 / EXPXXLMC0016 (same filter, several formats)
4¾" deep	~15⅜ × 24¼ × 4¾	Ultravation (91-005, 91-025)
4⅞" deep	~15⅝ × 24⅛ × 4⅞	Trion Air Bear Supreme 1400 (255649-105); Skuttle DB-25-16 (000-0448-001, 000-0448-005); GeneralAire 5FM1625 (MAC1400)
5¼" deep	15⅜ × 25½ × 5¼ (larger than nominal)	Goodman / Amana / Five Seasons / Clean Comfort / Electro-Air / Totaline (M1-1056, AMP-M1-1056, P102-1625, 918395)

The directional-depth rule: a shallower filter can seat in a deeper cabinet if you gasket or shim the gap, but a deeper filter will never fit a shallower cabinet — the door won't close, and forcing it bends the frame and breaks the seal. A real example: Lennox and Trion cross-list the 4⅜ Lennox X6670/X6672 filter as a replacement for the deeper Trion Air Bear Supreme 1400 (255649-105) — the shallower filter seats in the deeper Air Bear cabinet. The reverse won't work: the 4⅞ Air Bear filter won't seal in a 4⅜ Lennox or Carrier cabinet. And the Goodman-family M1-1056 is the only oversized 5¼ class (actually larger than nominal at 15⅜ × 25½), so it won't drop into any narrower cabinet.

One Carrier/Bryant clarification worth knowing: the pre-assembled box filter (FILXXCAR0016 in MERV 8, FILXXCAR0116 in MERV 11) and the EZ Flex are the same 4-5/16-inch filter in different formats — EXPXXFIL0016 is the media only, EXPXXUNV0016 adds the plastic end caps, and EXPXXLMC0016 is the media-with-frame version. They fit the same cabinets (EZXCAB016, MACA016, MPKA016, FILCAB016). The EZ Flex simply ships broken down and assembles to the same size, so a flat-packed EZ Flex kit is interchangeable with the box filter — you haven't got the wrong part. (Carrier's oversized 5¼ private label is a different number, CMF1625, matching the Goodman-family filter in the row above.)

How to Verify Your Filter Dimensions Before Ordering

Pull out your current filter and read the printed dimensions on the frame. Most manufacturers stamp both the nominal size and the actual measurements. If the print has worn off, grab a tape measure and record the length, width, and depth to the nearest eighth of an inch — depth is the number that separates the four classes above (4⅜, 4¾, 4⅞, or 5¼).

Compare those numbers against the spec sheet for any replacement you're considering. For a deeper breakdown of how nominal sizing works across all filter dimensions, the nominal vs. actual sizes reference guide walks through the full process.

16x25x4 vs 16x25x5: Are They Interchangeable?

This question comes up constantly, and the honest answer is: sometimes, but not always. Many filters labeled 16x25x4 and 16x25x5 share nearly identical actual depths (often both around 4⅜ inches) — when that's the case, they're functionally the same filter with different nominal labels. (The Carrier box even prints "approx. size 16 x 25 x 4" with an actual of 15¾ × 24¾ × 4-5/16 for a filter sold as 16x25x5.) But some 16x25x5 cabinets genuinely take a deeper slab (4¾ to 5¼ inches, per the table above). Stuffing a filter that's too thick compresses the pleats, restricts airflow, and shortens its life; one that's too thin leaves a bypass gap. Check your cabinet's internal depth with a tape measure rather than trusting nominal labels alone. If your cabinet measures roughly 4⅜ to 4½ inches deep, filters in either the 16x25x5 furnace filter or 16x25x4 HVAC filter categories should work.

16x25x5 Compatibility: Find Your Filter by Cabinet

The cabinet model — not the nominal size on the box — determines which filter actually fits. Here's how the common 16x25x5 cabinets map to the correct replacement:

• Lennox HCC16-28, Honeywell F-series & Carrier/Bryant (4⅜") — the most common 16x25x5 cabinets, all in the shallow class. For Lennox HCC16-28, use the Atomic X6670 MERV 11, the Atomic X6670 MERV 13 upgrade, or the Atomic X6672 MERV 16; the genuine Lennox X6670 OEM fits the same cabinet. For a Honeywell F-series media cabinet, use the Atomic FC100A1029 MERV 11 or FC200E1029 MERV 13. For a Carrier or Bryant cabinet (EZXCAB016, MACA016, MPKA016, FILCAB016) — whether you have the pre-assembled box filter (FILXXCAR0016 / FILXXCAR0116) or the flat-packed EZ Flex (EXPXXFIL0016 media, EXPXXUNV0016 with end caps, or EXPXXLMC0016 with frame), they're the same filter — use the Atomic EXPXXFIL0016 MERV 11 or MERV 13. This 4⅜ filter is also cross-listed by Lennox and Trion as a replacement for the deeper Trion Air Bear Supreme 1400 (255649-105) cabinet, and seats in it fine.
• Ultravation (4¾") — its own slightly deeper footprint. Match it with the Atomic-compatible Ultravation 91-005 (MERV 11) or 91-025 (MERV 13); genuine OEM is the Ultravation 91-005. Ultravation cabinets run 4¾″ — the Atomic Ultravation-compatible is the exact fit, and the 4⅞″ Skuttle-compatible below also seats well if that's what you have on hand (only ⅛″ deeper). Note: the 16x25x5 model is 91-005 / 91-025 — do not confuse it with the 20x25x5 model 91-006 / 91-026.
• Trion Air Bear, Skuttle & GeneralAire (4⅞") — the deep-media class. For a Trion Air Bear Supreme 1400 cabinet, use the Atomic Air Bear 255649-105 MERV 11 (or fit the shallower 4⅜ Lennox/Carrier filter above — this deep cabinet accepts both). For a Skuttle DB-25-16 cabinet, use the Atomic Skuttle 448-001 MERV 8, 448-005 MERV 11, or 448-005 MERV 13 upgrade (Skuttle went out of business in 2023, so these Atomic USA-made replacements are the fit). GeneralAire MAC1400 cabinets take the GeneralAire 5FM1625.
• Goodman, Amana, Five Seasons, Clean Comfort, Electro-Air & Totaline (5¼") — the only true oversized 16x25x5 class, physically larger than the others (15⅜ × 25½). It's one filter sold under several private labels; part numbers include M1-1056, AMP-M1-1056, P102-1625, and 918395. Use the Atomic M1-1056 MERV 11 or the M1-1056 MERV 13 upgrade. These are genuinely bigger than the Carrier/Bryant shallow filters above — don't substitute one for the other.

Always cross-reference the part number stamped on your existing filter or printed in your cabinet's documentation. Brand names alone aren't enough, since both Carrier and Lennox produce multiple cabinet depths across their product lines.

MERV 8 vs MERV 11 vs MERV 13 vs MERV 16: Picking the Right 16x25x5 Furnace Filter

MERV ratings tell you what particle sizes a filter captures — higher numbers trap smaller particles. In a thin 1-inch filter, a higher MERV also means more airflow resistance, so people learn to be cautious about it. In a 5-inch cabinet like the 16x25x5, that tradeoff mostly goes away: the deep pleats give the air so much more surface to pass through that you can choose MERV by your air-quality needs rather than worrying about your blower.

MERV 8: Solid Baseline for Most Homes

A MERV 8 filter captures dust, pollen, and mold spores effectively. For households without pets or allergy concerns, this rating delivers reliable protection for your HVAC equipment without adding measurable static pressure. It's the default recommendation from most equipment manufacturers, and frankly, it's enough for many homes.

MERV 11: The Sweet Spot for Pet Owners

MERV 11 adds meaningful capture of pet dander, finer dust, and some smog particles. If you have dogs, cats, or mild seasonal allergies, this is where the cost-to-benefit ratio peaks. The additional airflow resistance stays manageable for most residential blower motors.

MERV 13 and MERV 16: The High-Filtration Range

MERV 13 captures bacteria, tobacco smoke, and very fine particulate, and MERV 16 goes further still, trapping about 95% of the finest 0.3–1.0 micron particles, including wildfire smoke. Blanket buying guides often warn against high MERV, but that caution is really about thin 1-inch filters, where dense media does restrict airflow. In a 5-inch cabinet the math flips: the deep pleats spread air across so much surface that even MERV 16 keeps resistance low. An independently tested 5-inch MERV 16 came in around 0.07 in. w.c. at full airflow — lower than a 5-inch MERV 11 or 13, and far below a 1-inch MERV 13's roughly 0.30 in. w.c. So in a 16x25x5 you can run MERV 16 for the finest-particle and smoke capture without giving up airflow (see the airflow test data).

Here's the underlying reason: a 5-inch media filter at MERV 11 often performs comparably to a 1-inch filter at MERV 13 in terms of total dust holding capacity, because the deeper pleats provide far more surface area. That extra surface area means less pressure drop per square inch of media, which is one of the real advantages of whole-house 16x25x5 filters over standard 1-inch replacements.

How Often to Replace a 5-Inch Furnace Filter

Most 16x25x5 filters last 6 to 12 months, a significant upgrade from the 30- to 90-day cycle of 1-inch filters. Your actual replacement interval depends on household conditions.

A two-person household with no pets in a moderate climate can reasonably push toward 12 months. Add a couple of dogs or cats, and you're looking at 6 to 8 months. Heavy allergy sufferers, smokers, or homes near construction zones should check the filter every 4 to 6 months and replace it when the media looks uniformly gray and the pleats show visible debris buildup.

Future Market Insights projects that HVAC filters will account for 33.2% of total residential filter market revenue by 2026, which reflects how central furnace filtration has become to home maintenance. Staying on top of your replacement schedule protects both air quality and equipment longevity.

Whole-House Air Filter vs HVAC Air Purifier: Do You Need Both?

A 16x25x5 media filter handles particulate filtration for your entire duct system. It catches dust, dander, pollen, and (at higher MERV ratings) fine particles and some microorganisms. For most households, that's sufficient.

Standalone HVAC air purifiers and UV germicidal systems serve a different function. UV lights target biological contaminants like mold and bacteria on the coil surface, while electronic air cleaners use charged plates to attract particles. These systems complement a media filter rather than replace one. If someone in your home has severe respiratory conditions, adding UV treatment alongside a MERV 13 or MERV 16 whole-house media filter creates a layered defense. For everyone else, a quality media filter changed on schedule does the heavy lifting.

Frequently Asked Questions

Q: Are the Honeywell, Lennox, Ultravation, Carrier, and Skuttle 16x25x5 filters interchangeable?

A: Not automatically. They all carry the "16x25x5" nominal label but fall into four actual-size classes — 4⅜, 4¾, 4⅞, and 5¼ inches deep. Most brands sit in the 4⅜ shallow class: Lennox, Honeywell, and Carrier/Bryant, where the Carrier box filter (FILXXCAR0016 / FILXXCAR0116) and the Carrier EZ Flex (EXPXXFIL0016 / EXPXXUNV0016 / EXPXXLMC0016) are the same 4-5/16-inch filter in several formats. Ultravation runs 4¾, Air Bear / Skuttle / GeneralAire run 4⅞, and only the Goodman-family M1-1056 is the oversized 5¼ class. A shallower filter can be shimmed into a deeper cabinet, but a deeper or wider filter will not fit a smaller one. Match the actual dimensions or the cabinet part number, not just the nominal size.

Q: What's the difference between the Carrier box filter and the EZ Flex?

A: Nothing, filtration-wise — they're the same 4-5/16-inch Carrier/Bryant filter. The box version (FILXXCAR0016 in MERV 8, FILXXCAR0116 in MERV 11) ships pre-assembled. The EZ Flex ships broken down to save space, and comes in three forms: EXPXXFIL0016 is the pleated media on its own, EXPXXUNV0016 includes the reusable plastic end caps, and EXPXXLMC0016 is the media with its frame. Assembled, they all measure the same as the box filter and fit the same cabinets (EZXCAB016, MACA016, MPKA016, FILCAB016). Buy whichever format is cheaper or matches what your cabinet already uses.

Q: Does a higher-MERV 16x25x5 filter reduce my airflow?

A: In a 5-inch cabinet, not meaningfully — the deep pleats spread air across so much media that even MERV 16 stays low-resistance (an independently tested 5-inch MERV 16 measured about 0.07 in. w.c. at full airflow, lower than a 5-inch MERV 11 or 13). The airflow warnings you usually see are about thin 1-inch filters. If your airflow already feels weak, it is worth confirming your system's static pressure and duct sizing, but the MERV number itself is rarely the culprit at this depth.

Q: What is the best way to set reminders so I do not forget to replace a 16x25x5 filter?

A: Add a recurring calendar reminder based on your starting interval, then adjust it after the first change based on how dirty the filter looks. Many homeowners also write the install date on the filter frame and keep a spare on hand to avoid delays.

Q: How do I tell which side of a 16x25x5 filter faces the furnace or air handler?

A: Look for the airflow arrow printed on the frame, it should point toward the blower compartment. If there is no arrow, check the cabinet for an airflow label or take a photo of the old filter orientation before removing it.

Q: Can I run my HVAC system briefly if I do not have a replacement 16x25x5 filter yet?

A: Avoid running without a filter because dust can build up on the coil and blower, reducing efficiency and increasing wear. If you must run it temporarily, limit runtime and install the correct replacement as soon as possible.

Q: What should I do if my filter cabinet door will not close after installing a new 16x25x5 filter?

A: First confirm the filter is fully seated in the track and not catching on a gasket or latch. If it still will not close, the filter may be from a deeper class than your cabinet accepts, or the cabinet could be slightly out of square — in that case swap to the correctly sized model rather than forcing the door.

Q: Are washable or reusable 16x25x5 filters a good idea for whole-house systems?

A: Reusable filters can reduce ongoing purchases, but they often have lower fine-particle capture and performance depends heavily on thorough cleaning and drying. If consistent filtration and convenience matter most, a high-quality disposable media filter is typically the safer choice.

Q: How should I dispose of a used 16x25x5 furnace filter, especially if someone has allergies?

A: Slide the filter into a trash bag before carrying it through the house to minimize dust release, then seal the bag and dispose with household waste. If allergies are a concern, wear a mask and gloves, and consider changing the filter when the system is off to reduce airborne disturbance.

Get the Right 16x25x5 Filter on the First Try

Measure your cabinet, match it to one of the four depth classes above — 4⅜ (Lennox / Honeywell / Carrier box + EZ Flex), 4¾ (Ultravation), 4⅞ (Air Bear / Skuttle / GeneralAire), or 5¼ (Goodman family) — and pick a MERV rating that fits your household's air-quality needs. At 5-inch depth you can step up to the highest filtration without an airflow penalty. That simple process eliminates the most common buying mistakes with whole-house filters.

Atomic Filters carries 16x25x5 replacement filters for all four cabinet classes — Lennox, Honeywell, Carrier/Bryant, Ultravation, Trion Air Bear, Skuttle, and Goodman — with a full range of MERV options and savings up to 40% compared to OEM pricing. Backed by over 4,156 customer reviews and fast shipping, it's a straightforward way to keep your system running clean without overpaying for a brand name on the box.