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Actual Size: 15 1/2" x 24 1/2" x 3 5/8"
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Factory-Direct Low Prices, Made in the USA
Hassle-Free Returns & Free Exchanges
RESIDENTIAL AND/OR COMMERCIAL USE
Change Every 3 Months
Actual Size: 15 1/2" x 24 1/2" x 3 5/8"
Free Delivery Factory-Direct Low Prices, Made in the USAHassle-Free Returns & Free ExchangesRESIDENTIAL AND/OR COMMERCIAL USE
Change Every 3 Months
Actual Size: 15 1/2" x 24 1/2" x 3 5/8"
Free Delivery Factory-Direct Low Prices, Made in the USAHassle-Free Returns & Free ExchangesRESIDENTIAL AND/OR COMMERCIAL USE
Change Every 3 Months
If you are replacing a Honeywell 16x25x4 or 20x25x4, your Filterbuy replacement is a 5” filter.
The 5” Filterbuy replacement filter is trimmed down to the “actual” size of your original 4” Honeywell filter.
⚠️ Find your compatible filter by choosing one of the filters below. ⚠️
At Filterbuy, we don't cut corners—we craft high-quality air filters right here in the USA and ship them to your doorstep for free. No delays, no gimmicks—just clean air, made easy. With thousands of five-star reviews and filters built for real life & every HVAC system, it's no wonder why over 4 million families trust Filterbuy.
Proudly Made In The USA
Fast, Free Shipping on Every Order
Premium Materials That Go The Distance
85,000+ 5-Star Reviews From Happy Customers
Save Up to 70% Per Filter with Packs
Measure length × width × depth with a tape measure to find the actual size.
Round up each dimension to the nearest whole number to get the nominal size. Example: 15 1/2" x 24 1/2" x 3 5/8" in → 16x25x4 nominal.
Search by nominal size on our site for the best fit.
4″ filters offer better airflow and a longer life (6–9 months) than standard 1″ or 2″ filters — ideal for homes with pets or allergy concerns.
Sizing note:
If the filter you buy doesn't fit, we'll send you a better size.
MERV stands for Minimum Efficiency Reporting Value—but don't let the technical name fool you. It's just a way to rate how well an air filter traps stuff like dust, pollen, pet dander, and smoke. The higher the MERV number, the more particles it catches—and the cleaner your air will be.
Comparable to:FPR: 4-7
MPR: 600-1000
Dust & Debris
Dust Mites & Particles
Pollen
Mold
Lint
Dander
Comparable to:FPR: 6-9
MPR: 1200-1550
Dust & DebrisDust Mites & ParticlesPollenMoldLintDander
Smoke & Smog
Comparable to:FPR: 10
MPR: 1900-2800
Dust & DebrisDust Mites & ParticlesPollenMoldLintDanderSmoke & Smog
Bacteria
We build every Filterbuy filter to deliver reliable 90-day performance—thanks to smart design and premium materials that do the heavy lifting. Here's what makes the difference:
More pleats = more surface area to capture dust and debris, keeping your air cleaner longer.
Pleats are magnetized to attract and trap microscopic particles—like pet dander, pollen, and smoke.
Engineered to resist warping in extreme temperatures and high humidity.
A layer of metal reinforcement keeps pleats evenly spaced and structurally sound—no sagging, even at high airflow.
Assembled with care. Built to perform. Ships fast, free, and reliably from our U.S. facilities.
Turn Off Your HVAC SystemSafety first.
Remove The Old FilterLook for the airflow arrow and make note of the direction.
Slide In Your New FilterArrow should point toward the system (same direction as before).
Turn Your System Back OnAnd enjoy the fresh, clean air.
Not all air filters are created equal. Pleated filters don't just last longer—they actually clean your air better. Here's how they stack up:
Efficiency:
High (MERV 8–13) – Traps more particles
Lifespan:
90 days – Long-lasting performance
Air Quality:
Excellent – Cleaner, healthier air
Materials:
Recyclable and durable
Efficiency:
Low (MERV 4 or less) – Misses small stuff
Lifespan:
30 days or less – Replace often
Air Quality:
Minimal – Basic protection only
Materials:
Thin, flimsy, and not recyclable
Pleated filters are a no-brainer—more protection, less hassle, and better air for your home.
Changing your filter on time keeps your HVAC system running efficiently—and helps protect your lungs from dust, allergens, and airborne irritants. Here's how often to swap it out based on your needs:
For most homes without pets or special air quality concerns. Great for general upkeep and energy efficiency.
Shedding fur, dander, and allergy triggers can build up fast. Changing your filter every two months helps keep the air fresher and symptoms at bay.
For households affected by smoke, pollution, or respiratory conditions, monthly changes ensure maximum protection.
| Nominal Size | 16 x 25 x 4 inches |
| Actual Size | 15 1/2" x 24 1/2" x 3 5/8" inches |
| Filter Type | Pleated |
| Media | Electrostatically Charged |
| Frame | Beverage Board |
| MERV Ratings Available | 8, 11, 13 |
| Lifespan | Up to 12 Months |
| Origin | Made in USA |
Filterbuy 16x25x4 MERV 8 filters make your home's air cleaner. These filters capture airborne contaminants and make sure cleaner air circulates indoors.
They also help your HVAC work better. Less dust means lower energy bills and a longer lasting unit. The sturdy frame resists warping. This makes it a reliable choice for your home.
Stick around to learn more about why these filters are worth it!
Filterbuy 16x25x4 MERV 8 filters make your air cleaner as it traps things like dust mites and pet dander.
This lowers HVAC strain and utility bills.
Frequently applying these filters adds more life to HVAC, which does not allow dust to collect and propagate stress.
The robust frame ensures that the filters cannot fold or warp in any way, thereby facilitating proper filtration and being the most durable.
Balancing performance with cost-effectiveness, these filters offer a significant upgrade for homes without notably restricting airflow.
MERV ratings measure air filter efficiency. They help maintain HVAC performance. The American Society of Heating, Refrigerating and Air Conditioning Engineers or ASHRAE created this method. It aims to standardize efficiency across brands and models.
Filterbuy MERV 8 filters offer a good balance of performance and cost. It captures most household pollutants without restricting airflow. It catches tiny particles, from 3.0 to 10.0 micrometers, like dust mites, mold spores, and pet dander.
The Filterbuy 4-inch filters like 16x25x4 MERV 8 filters are a great choice for home HVACs.
Size: Nominal size is 16x25x4. Actual dimensions are 15.50x24.50x3.63" for a snug fit. Check your system’s requirements before buying.
Material: Made with synthetic media for strong filtration and good airflow. It captures airborne contaminants to improve indoor air cleanliness. The sturdy frame resists warping and collapsing.
Lifespan: Lasts up to three months. Check monthly, especially during heavy use. Replace when dirty to maintain clean air and HVAC efficiency.
Indoor air quality affects your health and comfort. Many pollutants, like dust and chemicals, are ignored. However, they can still harm your respiratory system.
Common sources include cleaning products, paint, and furniture. These trigger allergies. They also worsen asthma and cause long term respiratory issues.
Simple steps like regular cleaning and ventilation help. However, high quality air filters make the biggest difference. Filterbuy 16x25x4 MERV 8 filters capture most indoor pollutants. They create a healthier and more comfortable home. Investing in better filters means investing in your well being.
MERV 8 filters save energy by letting air flow easily while still cleaning it. They reduce strain on your HVAC. And this lowers energy costs.
Regular maintenance is key. Dirty filters make the system work harder. This increases energy use and raises utility bills. Replacing MERV 8 filters on time keeps your system efficient. It also helps reduce expenses.
The combination of regular maintenance and MERV 8 filters prolongs the life of your HVAC. Timely filter changes do more than clean your air.
Routine care prevents dust and allergens from building up. This reduces strain on your system, preventing unnecessary wear and tear. A Filterbuy 16x25x4 MERV 8 filter adds extra protection to extend your HVAC’s life.
Key benefits of MERV 8 filters:
Fewer Repairs: Less strain means less breakdowns and repairs.
Longer Lifespan: A well maintained HVAC lasts longer, saving you money over time.
Better Performance: Regular filter changes keep your HVAC efficient and your home cozy all year round.
Filterbuy offers high-performance filters that enhance air quality and HVAC efficiency. With a focus on quality and convenience, they ensure you get the best value for your filtration needs.
Key Benefits:
Fast order processing with nationwide shipping
Affordable subscription service for regular deliveries
100% American-made filters
Easy installation with clear instructions
Filters that last up to 3x longer than fiberglass alternatives
Yes. It can effectively capture large-sized particles such as dust, pollen, and mold spores. So, for most residential or light commercial applications, it works out. For those areas that demand high levels of air purity, homes with allergic people, or some medical facilities, MERV 8 may not be sufficient.
With a MERV 8 filter, there is some restriction to the flow of air, although it is specifically designed to have the filtration efficiency balance out the airflow. It can slightly negatively affect the airflow but generally does not affect performance for most residential settings.
A MERV 8 filter is about equivalent in particle capture range to the higher end of filters in common use in a residential environment. These are usually compared to basic pleated filters, which are generally effective for normal household dusts and debris.
Not all MERV 8 pleated filters are the same; materials, construction, and overall quality can be different. Some may have more stamina than others or be somewhat more effective at a higher end of the spectrum in MERV 8, so one does need to be aware of brand and specification when choosing a filter.
The downside of using high MERV filters includes extreme hindrance to airflow, hence straining the HVAC systems and reducing their general efficiency. This could probably lead to a surge in energy costs and, in due time, involve more maintenance than needed.
MERV ratings between 6 and 8 are usually the sweet spot for most residential HVAC systems, providing good airflow while turning over effective filtration. This range offers a good balance between air quality and system performance.
MERV 8 air filters would differ in replacement. Change every 1 to 3 months, which would depend on usage, pets, or air quality. Regular replacement ensures optimal performance and quality of air.
MERV 11 was far superior in capturing finer dust, pollen, and some bacteria. MERV 8 filters would be adequate for general residential applications and provided better airflow, hence being more energy-efficient.
MERV 11 are not too high for residential applications; however, it can again create more restriction to airflow compared to lower-rated filters. This may lead to some extra load on the HVAC system. It is best if you refer to your HVAC system specification to determine the maximum MERV rating your system can be able to handle effectively.
HEPA filters have always been more effective in filtering really small particles. That includes most of the allergens, bacteria, and viruses, compared to MERV filters. However, HEPA filters tend to be much more resistant to air flow and may require modifications in most HVAC systems.
Yes, the MERV 8 filter provides sufficient filtration by catching large dust particles in the air, so it fits for improving general air quality by reducing household dust in residential areas.
Yes. MERV 8 can filter mold spores. The normal size of mold spores is within the specifications that MERV 8 filters are set to capture. It's good for decreasing mold spores in the air. Although higher MERV ratings would serve the purpose more effectively.
