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Actual Size: 11.25x11.25x1"
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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: 11.25x11.25x1"
Free Delivery Factory-Direct Low Prices, Made in the USAHassle-Free Returns & Free ExchangesRESIDENTIAL AND/OR COMMERCIAL USE
Change Every 3 Months
Actual Size: 11.25x11.25x1"
Free Delivery Factory-Direct Low Prices, Made in the USAHassle-Free Returns & Free ExchangesRESIDENTIAL AND/OR COMMERCIAL USE
Change Every 3 Months
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: 11.25x11.25x1" in → 11.25x11.25x1 nominal.
Search by nominal size on our site for the best fit.
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 | 11.25 x 11.25 x 1 inches |
| Actual Size | 11.25 x 11.25 x 1" inches |
| Filter Type | Pleated |
| Media | Electrostatically Charged |
| Frame | Beverage Board |
| MERV Ratings Available | 8, 11, 13 |
| Lifespan | Up to 90 Days |
| Origin | Made in USA |
At Filterbuy, we’ve seen firsthand how hard it is for homeowners to find uncommon filter sizes—like 11.25x11.25x1—without compromising on performance or quality. That’s exactly why we custom-manufacture these MERV 11 HVAC and furnace filters in our family-run U.S. facility, where every filter is rigorously crafted and tested for exact fit and filtration efficiency. Based on years of working with homeowners dealing with allergies, pet dander, and system inefficiencies, we developed this filter to exceed industry standards—offering protection against up to 95% of airborne particles without choking your airflow. This page gives you everything you need to confidently choose the right filter, backed by our experience, data, and commitment to clean, healthy air.
Perfect fit matters. 11.25x11.25x1 MERV 8 filters ensure proper airflow and performance.
Cleaner indoor air. Captures up to 90% of dust, dander, and mold spores.
Save on energy. Clean filters can reduce HVAC energy use by up to 15%.
Made by experts. Built, tested, and trusted by Filterbuy’s in-house team.
Easy to order. Fast shipping, auto-delivery, and helpful support included.
When it comes to maintaining clean, healthy indoor air, the right air filter size and efficiency level make all the difference. Filterbuy’s 11.25x11.25x1 MERV 11 HVAC and furnace air filters are specifically designed for homes that require a less common, precision-cut size without sacrificing filtration performance.
With a MERV 11 rating, these filters capture up to 95% of airborne particles—including dust, pollen, pet dander, mold spores, and smoke—making them ideal for families with allergies, pets, or sensitivity to poor air quality. Unlike lower-grade filters that let fine particles slip through or clog quickly, our pleated design ensures longer-lasting airflow and efficiency.
What sets Filterbuy apart? Every filter is made-to-order in our Alabama-based facility using high-quality, American-made components. We don’t outsource, cut corners, or rely on one-size-fits-all solutions—because we know your home’s comfort and air quality depend on fit, reliability, and performance. Fast shipping, bulk pack options, and auto-replacement scheduling make it easy to stay on top of filter changes year-round.
Choose Filterbuy and breathe easier—because clean air starts with the right filter, made by people who care.
“We created our 11.25x11.25x1 MERV 11 filters because we kept hearing from homeowners who were frustrated by limited sizing options and flimsy off-the-shelf products. After years of working directly with HVAC professionals and families managing allergies and pet dander, we engineered a filter that fits precisely, performs consistently, and holds up longer—because clean air shouldn’t be a compromise.”
Source: EPA
Poor indoor air can contain allergens, dust, mold spores, and more.
Source: NIEHS
Clean air filters help protect against long-term indoor exposure.
Source: CDC
MERV 11 filters are ideal for homes with asthma or allergy concerns.
Why it matters: Choosing the right air filter isn’t just about fit—it’s about protecting your home’s air and your family’s health.
Here’s what sets Filterbuy’s 11.25x11.25x1 MERV 11 filters apart:
✅ Custom fit for rare sizes—no more compromising with ill-fitting filters.
✅ High-performance MERV 11 rating—captures up to 95% of airborne particles.
✅ Made in the USA—crafted in-house, never outsourced or mass-produced.
What we've learned from experience:
Poor filtration impacts more than your HVAC—it affects sleep, breathing, and everyday well-being.
Homeowners with allergies, asthma, or pets see the biggest difference with MERV 11 filters.
Long-lasting filters help reduce HVAC strain and cut long-term energy costs.
Our opinion:
🔹 Air filters aren’t just maintenance—they’re protection.
🔹 Investing in a high-quality filter is investing in cleaner air, better comfort, and long-term peace of mind.
Check your filter size
Pick your pack
Choose single or multi-pack options for better value.
Plan your replacements
MERV 11 filters last up to 90 days.
Set a reminder or use auto-delivery for convenience.
Fast shipping. U.S.-made quality. No middlemen.
Learn more if needed
Visit our Resource Center for guides, tips, and FAQs.
Our filters are custom-made in the U.S. using high-quality pleated media that captures up to 95% of airborne particles. Unlike off-the-shelf filters, our exact-fit design prevents air bypass and ensures consistent airflow and performance.
Yes. MERV 11 filters provide advanced filtration without restricting airflow in most residential systems. They are ideal for homes with pets, allergies, or higher air quality needs. Always check your HVAC manufacturer’s guidelines for compatibility.
We recommend replacing it every 2–3 months. If you have pets, allergies, or live in a high-dust area, monthly replacement may be more effective for maintaining optimal air quality.
Yes! Filterbuy.com offers a convenient auto-delivery option so you never forget to change your filter. You can customize the delivery schedule to match your replacement needs.
Check the size printed on your existing filter or measure the actual filter slot. You can also reach out to Filterbuy’s customer service for sizing help before you order—our team is happy to assist!
