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Actual Size: 16.5x19.5x3.75"
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Made in the USA
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Available In MERV Rating: 8, 11, 13
Made in the USA
Ships in 24 hours
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 MERV 8 |  MERV 11 |  MERV 13 | |
|---|---|---|---|
| Best for | Standard Residential/Commercial Healthy Families | Superior Residential/Commercial Allergy Sufferers | Optimal Residential/Commercial Hospital Grade |
| Comparable ratings | MPR 600 & FPR 5 | MPR 1000-1200 & FPR 7 | MPR 1500 - 1900 & FPR 10 |
| Filtration | Captures 90% of Airborne Particles | Captures 95% of Airborne Particles | Captures 98% of Airborne Particles |
| Dust, lint & debris | |||
| Mold, pollen | |||
| Dander, dust mites | |||
| Smoke & Smog | |||
| Bacteria | |||
| Odor, vocs |
Generally, we recommend you replace your air filters every 90 days. Find out below if you should change your filters more often.
Change your filter every
6 weeks
to ensure indoor air quality is at its best.
Change your filter every
2 months
to avoid shedding and odor buildup.
Change your filter every
2-3 months
as having clean air is even more important with children in your home.
Change your filter every
6 weeks
to ensure indoor air quality is at its best.
Change your filter every
2 months
to avoid shedding and odor buildup.
Change your filter every
2-3 months
as having clean air is even more important with children in your home.
Clean air makes a big difference in your home. With Filterbuy air filters 17x20x4, you can keep your indoor air fresh and healthy while protecting your HVAC unit. The in-house production of each filter involves durable materials which are sourced from the US to guarantee accurate fitting and long-lasting performance. In addition to this, the filters were designed to capture as much as 98% of all airborne particles, including dust, pollen, and so on, which consequently leads to the improvement of air quality and the efficiency of HVAC systems. Air filters from Filterbuy not only provide easier breathing but also a cleaner home.
A 17x20x4 air filter is a 4-inch-deep pleated HVAC filter measuring 17 inches by 20 inches, designed for whole-home air handlers and media cabinets that accept thicker filters. Compared to standard 1-inch filters, the 4-inch depth packs in significantly more pleated surface area — meaning better particle capture, stronger airflow, and a longer service life (typically up to 90 days versus 30).
Key facts at a glance:
Actual size: Filterbuy 17x20x4 filters are built to nominal size for a precise, snug fit (no air bypass).
MERV options: MERV 8 (everyday dust and lint), MERV 11 (pets, pollen, allergens), MERV 13 (fine particles, smoke, virus-sized particulates).
Captures: Up to 98% of airborne particles.
Lifespan: Up to 90 days per filter — about 3x longer than 1-inch fiberglass.
Made in: USA, factory-direct from Filterbuy with free shipping.
Best for: Homeowners with deeper filter slots who want fewer changes, cleaner air, and easier HVAC operation.
If your existing filter measures roughly 17" x 20" x 4" (or your slot is 4 inches deep), this is your size — and a higher MERV upgrade is the simplest way to noticeably improve indoor air quality without replacing equipment.
Better Filtration
98% of airborne particles are captured, providing cleaner and healthier air.
Precision Fit and Quality
Custom-sized, USA-made, and built with durable materials.
MERV Options for Every Need
MERV 11 - For homes with pets/allergies
MERV 13 - Captures finer particles, including viruses
Filterbuy air conditioner filters 17x20x4 are custom-built to deliver long-lasting performance and superior filtration. Each filter is proudly made in the USA using high-capacity pleated media that captures up to 98% of airborne particles without restricting airflow.
Available in multiple MERV ratings, including MERV 8, 11, and 13 our filters meet a variety of needs.
MERV 8 - Basic dust protection
MERV 11 - For homes with pets/allergies
MERV 13 - Captures finer particles, including viruses
Unlike fiberglass alternatives, Filterbuy 17x20x4 air filters for allergies feature industrial-grade frames that won’t bend, warp, or collapse even in high-humidity environments.
Filterbuy ensures quick shipping, seamless online ordering, and precise sizing so you get the performance you need when you need it.
Filterbuy Filters Ensure Optimal HVAC Operation
Have you ever wondered how Filterbuy 17x20x4 pleated filters ensure smooth operation for your HVAC? Here are our points!
Filterbuy filters maintain consistent airflow. This is the reason your HVAC won't be overworked.
They are very effective in blocking dust and debris, thus preventing internal components from getting damaged.
When the filters are clean, there is less strain on the HVAC, which in turn increases its lifespan.
Through optimal filtration, one ensures the heating and cooling that is energy and money-saving.
"After shipping millions of filters to homes across the country, we've learned the same thing every time: the homeowners who get the cleanest air aren't the ones who spend the most — they're the ones who get the size right, pick a MERV that matches their life, and stop thinking about it. A 4-inch filter does exactly that."
— Filterbuy Air Quality Team
Look — picking a 17x20x4 filter shouldn't feel like cramming for an exam. But a little homework up front means cleaner air, lower bills, and an HVAC that doesn't quit on you in August. We've rounded up the seven sources we trust most, so you can skip the guesswork and shop like a pro.
The EPA's homeowner-friendly walkthrough of how air filters actually work, what they catch, and how to match one to your home. No jargon, no fluff — just the basics done right. Source: U.S. Environmental Protection Agency — Guide to Air Cleaners in the Home https://www.epa.gov/indoor-air-quality-iaq/guide-air-cleaners-home
MERV ratings aren't complicated once someone explains them clearly. The EPA does exactly that — and tells you why MERV 13 is the gold standard when your system can handle it. Source: U.S. Environmental Protection Agency — What is a MERV Rating? https://www.epa.gov/indoor-air-quality-iaq/what-merv-rating
If you've got allergies, asthma, or someone vulnerable under your roof, this one matters. The CDC lays out exactly how filtration fits into a healthy-home strategy — and why a higher MERV is worth the upgrade. Source: Centers for Disease Control and Prevention (NIOSH) — Ventilation FAQs https://www.cdc.gov/niosh/ventilation/faq/index.html
Every MERV rating you'll see on a filter package traces back to ASHRAE's official testing standard. Want to know whether a brand's claims actually hold up? Go straight to the source. Source: American Society of Heating, Refrigerating and Air-Conditioning Engineers — Standards & Guidelines https://www.ashrae.org/technical-resources/standards-and-guidelines
The Department of Energy spells out what a clogged filter actually does to your system — and it's not pretty. A few minutes here will save you a service call later. Source: U.S. Department of Energy — Air Conditioner Maintenance https://www.energy.gov/energysaver/air-conditioner-maintenance
ENERGY STAR's straight-talk checklist on filter changes, airflow, and the small habits that quietly cut your monthly costs. This is where 4-inch filters earn their keep — fewer changes, better airflow, real savings. Source: U.S. EPA ENERGY STAR — Heat & Cool Efficiently https://www.energystar.gov/saveathome/heating-cooling
The Asthma and Allergy Foundation of America has been helping families breathe better since 1953. Their guide cuts through the noise on what actually works against pollen, dander, dust mites, and smoke. Source: Asthma and Allergy Foundation of America — Air Cleaners: What You Need to Know https://community.aafa.org/blog/air-cleaners-what-you-need-to-know
Top industry data proves that high-performance filters improve air quality and health. System performance becomes elevated and optimized.
1. Air Quality is Improved by Filters that are High-Efficiency
The EPA confirms MERV rated filters reduce fine particles. PM2.5 triggers asthma and heart conditions.
Source: EPA.gov – Air Cleaners and Air Filters
2. Better Filtration Means Better Air Quality Control
The EPA recommends upgraded filters or portable air cleaners to control indoor air pollution.
Source: EPA.gov – Guide to Air Cleaners
3. Higher MERV Ratings Results to Healthier Homes
CDC recommends MERV 13 for better filtration, especially where outdoor air options are limited
Our MERV 13 filters trap smaller particles, including airborne viruses and fine pollutants
Many customers report fresher air and fewer allergy symptoms after upgrading
Source: CDC
Free, Super Fast Shipping — Sometimes next-day.
Buy packs, get up to 70% off each filter.
These filters actually last for 90 days — way longer than cheap fiberglass versions.
Made right here in the USA with super high-quality materials.
Auto Delivery option —save another 5%, and you'll never forget to replace your filters again.
Super Easy, Super Affordable.
You've got the research. Here's how to turn it into cleaner air — fast.
Check the dimensions printed on your current filter's frame.
Measure your filter slot: length, width, and depth.
Round up to the nearest inch if measurements fall short.
A snug fit matters — gaps let unfiltered air bypass the filter.
MERV 8 — Everyday dust, lint, and pollen.
MERV 11 — Pets, mild allergies, higher dust levels.
MERV 13 — Fine particles, smoke, virus-sized particulates (CDC/EPA recommended).
Not sure? MERV 11 fits most homes without straining your system.
Most modern systems handle MERV 13 — especially with a 4-inch filter.
Older unit? Check the manufacturer's guide or ask your HVAC tech.
Five minutes here saves a service call later.
Buy packs of 4 or 6 to save up to 70% per filter.
A 4-inch filter lasts up to 90 days — a pack of 4 covers a full year.
Save an extra 5% on every order.
Filters ship right when you need them.
Cancel or adjust anytime — zero commitment.
Set a 90-day phone reminder or mark the calendar.
Clean filters = better air, lower bills, longer HVAC life.
Yes. Your air filter must fit tightly in the slot. A loose filter lets air escape. This reduces cleaning efficiency.
No. MERV 11 works well for most homes. It helps remove more allergens. But it may slow airflow in older units.
It won’t filter the air properly. It causes poor air quality, wasted energy, and long-term damage.
Measure the length, width, and thickness of your old filter or the filter slot. Round each number up to the nearest inch.
Choose MERV 8 for normal dust. Pick MERV 11 if you want cleaner air or have pets and allergies.
Most HVAC experts recommend MERV 8 to 13. MERV 8 works for general use, while MERV 11 or 13 is better for allergies or asthma.
No. Stacking filters blocks airflow and harms your HVAC unit. Always use one filter with the correct thickness.
MERV 8 works well for households with no special air quality concerns. It filters common allergens like dust, pollen, and lint effectively.
MERV 8 filters should be changed every 2 to 3 months. Frequency depends on household conditions like pets, allergies, and usage.
High MERV filters restrict airflow if your HVAC isn’t designed for them. This can lead to reduced efficiency and potential equipment strain.
The best filter balances filtration quality and airflow, typically MERV 8 to 11 for most homes. Check your AC manufacturer’s guidelines for compatibility.
One of the most common HVAC filter sizes is 16x25x1. However, sizes vary, so it's important to check your unit's specifications.
Buy directly from trusted online suppliers. Filterbuy.com is a great source. This saves you time. You do not have to search many stores.
Filterbuy.com is your most reliable source. They specialize in a wide variety of air filter sizes, including the best 17x20x4 air filter, and offer direct shipping.
Get cleaner air, a happier HVAC, and up to 70% off when you buy in packs — shipped free, factory-direct, and built right here in the USA. Shop 17x20x4 filters now → and breathe easier in days, not weeks.
