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Actual Size: 19 1/2" x 24 1/2" x 3 5/8"
Free Delivery 
Factory-Direct Low Prices, Made in the USA
Hassle-Free Returns & Free Exchanges
RESIDENTIAL AND/OR COMMERCIAL USE
Change Every 3 Months
Actual Size: 19 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: 19 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: 19 1/2" x 24 1/2" x 3 5/8" in → 20x25x4 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 | 20 x 25 x 4 inches |
| Actual Size | 19 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 |
The Filterbuy 20x25x4 MERV 13 pleated air filter is a powerhouse. It keeps your HVAC clean and traps tiny particles. Thanks to its MERV 13 rating. The pleated design increases surface area. This allows the filter to trap more particles. It also promotes efficient airflow. This helps your system perform optimally and last longer.
Filterbuy 20x25x4 MERV 13 pleated air filter captures small particles. This improves indoor air and lowers allergens.
Increases filtration and airflow. This reduces strain on HVAC units.
Enhances air quality. This provides relief for allergy sufferers and reduces health risks.
Reduces dust buildup, extending HVAC lifespan and lowering maintenance.
Easy upgrade with noticeable benefits after installation.
Filterbuy 20x25x4 comes with a MERV 13 score, positioning it toward the top of the filtration scale. This score indicates that particles ranging from 0.3 to 1.0 microns are no match. In comparison, human hair diameters range around 50 to 70 microns, showcasing its exceptional performance in capturing minute particles.
Filtration efficiency is just one aspect to consider. It's also important to consider factors like airflow resistance and energy efficiency. This product strikes a balance, providing exceptional filtration while maintaining tolerable airflow resistance.
Other MERV scores include Filterbuy 20x25x4 MERV 8 which is versatile for many homes. Filterbuy 20x25x4 MERV 11 filter suits homes with allergy sufferers and pets.
Filterbuy 4-inch filters like 20x25x4 MERV 13 pleated filters offer superior filtration due to their increased surface area.
Unlike flat filters, the pleats trap more particles without restricting airflow. This improves energy efficiency by reducing HVAC workload. Their durable construction and longer lifespan make them an affordable choice.
Top quality filters, like Filterbuy 20x25x4 MERV 13, offer health benefits. They promote cleaner air, leading to cleaner, healthier air and fewer potential health issues. This means fewer trips to the doctor.
People with allergies or asthma will find Filterbuy filters especially helpful in reducing airborne contaminants. They help everyone breathe easier.
Air filters of high efficiency like this one notably lengthen the operational life of HVAC systems.
For four reasons, this is true:
educed strain on systems: High efficiency filters trap more particles. Reducing the HVAC load and preventing premature wear.
Enhanced performance: Clean filters enhance airflow. This increases efficiency and saves energy.
Less maintenance: Fewer particles entering the system means less frequent maintenance, saving time and money.
Breakdown prevention: Cleaner units are less likely to break down. This evades costly repairs or replacements.
Enjoy cleaner air and a longer lasting HVAC with the Filterbuy 20x25x4 MERV 13 air filter. It traps tiny particles and helps your system run more efficiently.
Replacing the filter is simple. First, check the airflow direction on the filter’s frame, placing the pleated side toward incoming air. Turn off the HVAC, remove the old filter, and insert the new Filterbuy filter. Ensure a snug fit, replace the cover, and restart the system. Enjoy cleaner air with the MERV 13 filter from Filterbuy.
Filterbuy provides high-performance filters designed to improve air quality and HVAC efficiency. With a commitment to quality and convenience, Filterbuy ensures you receive the best value for your air filtration needs.
Key Benefits:
Rapid order fulfillment with nationwide distribution
Affordable subscription service for regular deliveries
100% American-made filters
Simple installation with easy-to-follow instructions
Longer-lasting filters, lasting up to 3x longer than fiberglass alternatives
They last anywhere from 60 to 90 days. This varies based on usage and environmental conditions. Consistent maintenance tips include regular inspection and timely replacement to ensure optimal performance.
While it filters out smaller particles, it also strains systems not designed for such high-rated performance. This could potentially lead to increased energy usage and maintenance costs. It's crucial to verify your system's compatibility with this equipment.
While a 20x25x4 may fit physically, it might not perform efficiently if your system works for a 20x25x5. Always consult your system manual or a professional before changing sizes.
It requires replacement every 60-90 days to maintain its optimal performance. This depends on the air quality in your location. Failing to follow these requirements leads to reduced airflow and efficiency, potentially damaging your HVAC and negatively affecting your indoor air quality.
The exact lifespan of this equipment varies based on factors like usage and indoor air pollution levels. Therefore, while they boast superior efficiency and durability, their maintenance should still be a priority.
These equipment have a higher density to trap tiny elements, which deliberately restricts the flow of air. However, this does not mean you should avoid using it. They provide excellent air quality, capturing pollutants that lower-rated ones cannot. Therefore, the key lies in regular maintenance.
Always consider your specific needs, such as allergies or the presence of pets, when choosing a rating. Ultimately, the best one for your filter is one that provides good air quality without straining your system.
Its lifespan ranges from 30 to 90 days. Depends on usage and environmental factors. If you have pets, allergies, or live in a dust-prone area, increase the maintenance frequency.
Even though this equipment costs more, the long-term benefits, such as reduced need for system maintenance due to cleaner system components, offset the initial expense. Investing in a higher MERV filter provides a healthier living environment, savings in the long term, and an overall better performance.
Despite the higher upfront cost, expensive ones often boast longer lifespans compared to their less expensive counterparts. This longevity ties directly into maintenance, high-end ones require fewer changes due to their superior build and filtration capacity.
Their lifespan varies greatly depending on type, use, and environment. Pleated filters, for example, generally last longer than fiberglass ones due to their denser material. HEPA filters, renowned for their superior air purification, also have a considerable lifespan. However, longevity comes with maintenance.
High-quality ones may last longer, but if your home has a lot of dust or pet dander, or if someone in your household has allergies or respiratory problems, more frequent changes may be needed. Superior air quality reduces health risks and enhances comfort.
