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Actual Size: 11.25x11.25x0.75"
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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: 11.25x11.25x0.75"
Free Delivery Factory-Direct Low Prices, Made in the USAHassle-Free Returns & Free ExchangesRESIDENTIAL AND/OR COMMERCIAL USE
Change Every 3 Months
Actual Size: 11.25x11.25x0.75"
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: 11.25x11.25x0.75" 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 0.75" 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 |
Finding high-efficiency air filters in a rare size like 11.25x11.25x1 can feel like searching for a needle in a haystack—but at Filterbuy.com, it’s our specialty. Over the years, we’ve heard from thousands of homeowners frustrated by limited sizing options and poor filtration performance in generic filters. That’s why we engineered our MERV 13-rated 11.25x11.25x1 HVAC & furnace filters to deliver medical-grade air quality in a compact form factor—perfect for homes where space is tight, but clean air is non-negotiable.
Backed by real-world testing in our U.S.-based facilities and refined through customer feedback, these filters capture up to 98% of microscopic particles, including pollen, pet dander, mold, and even airborne viruses. If you’ve ever settled for less because your system required a hard-to-find size, this page will show you what it means to choose precision, protection, and peace of mind—direct from the source.
Exact Fit: 11.25x11.25x1 MERV 13 filters made for hard-to-find systems.
Superior Filtration: Captures up to 98% of allergens, dust, and bacteria.
Tested & Trusted: Backed by lab testing and real customer use.
Fast, Direct Shipping: Made in the USA and shipped from our factory.
Health-Focused: Ideal for homes with pets, allergies, or asthma.
When it comes to protecting your home’s air quality, size shouldn’t limit performance. Filterbuy’s 11.25x11.25x1 MERV 13 HVAC and furnace air filters are custom-built for systems requiring this less common dimension—without sacrificing filtration power. Engineered with electrostatically charged pleated media and a durable dual-wire backing, these filters capture up to 98% of airborne particles, including smoke, bacteria, pollen, and fine dust.
Ideal for households with allergies, pets, or heightened air quality concerns, our MERV 13 filters are recommended by industry experts for their balance of airflow efficiency and contaminant capture. Proudly made in the USA and shipped directly from our factory to your door, Filterbuy ensures consistent quality, fast delivery, and dependable protection with every order.
Whether you’re replacing your current filter or upgrading your home’s defense against pollutants, this filter delivers cleaner air, greater peace of mind, and the reliability you expect from a trusted brand.
"We've seen firsthand how overlooked filter sizes like 11.25x11.25x1 can lead homeowners to settle for poor air quality—or worse, force-fit the wrong filter. That’s exactly why we manufacture these MERV 13 filters to exact specs, so families don’t have to compromise. Clean air should be a standard, not a struggle—and we're proud to deliver that with every shipment."
Indoor air pollution is 2 to 5 times worse than outdoor air.
In some cases, it can be 100 times more polluted. 🔗 EPA – Indoor Air Quality
Remove 90%+ of particles in the 1–3 micron range (like bacteria, smoke, and droplets).
Recommended for homes concerned about health and clean air. 🔗 ASHRAE – Filtration Guidance
Common triggers include pollen, pet dander, and mold spores.
MERV 13 filters help reduce exposure indoors. 🔗 AAFA – Allergy Facts
Why This Filter Stands Out
11.25x11.25x1 MERV 13 filters aren’t generic—they’re custom-engineered for homes needing uncommon sizes.
Designed to offer high-performance filtration without compromising airflow or fit.
What We've Learned First-Hand
Many homeowners settle for poor-quality filters due to sizing constraints.
HVAC pros struggle to find reliable specialty-sized filters that meet modern air quality needs.
Here’s What Makes the Difference
Peace of mind: Ideal for homes with allergies, pets, or respiratory concerns.
Real customer results: Improved air quality and comfort within weeks of switching.
Performance-tested: Outperforms standard filters in particle capture and longevity.
Our Take? If you’re tired of compromising on indoor air quality just because of filter size, this is your solution. At Filterbuy, we build filters based on real-world experience and direct customer feedback—so you get precision, protection, and performance in every shipment.
1. Check Your Filter Size
Confirm that your HVAC system uses 11.25x11.25x1 filters.
Need help? Use our Filter Size Guide.
2. Choose MERV 13 for Best Protection
Great for allergy-sensitive homes and clean-air priorities.
3. Place Your Order
Click “Add to Cart” to buy directly from Filterbuy.
Enjoy fast U.S. shipping and optional auto-delivery.
Pro Tip: Set up a subscription so you never forget to replace your filters.
MERV 13 is a high-efficiency filtration rating that captures up to 98% of airborne particles, including pollen, mold, bacteria, and smoke. It's ideal for homes with allergy sufferers, pets, or health-conscious families seeking cleaner indoor air.
No, it’s considered a non-standard or custom size. Many retail stores don’t carry it, but Filterbuy manufactures this exact size to fit your system perfectly without modifications.
We recommend changing your filter every 3 months. However, homes with pets, allergies, or heavy HVAC usage may benefit from more frequent replacements—every 1–2 months.
Filterbuy’s MERV 13 filters are engineered for optimal airflow while delivering superior filtration. As long as your system supports high-efficiency filters, they won’t cause performance issues.
Unlike mass retailers, Filterbuy offers factory-direct, made-in-the-USA filters, including rare sizes like 11.25x11.25x1. You get custom fit, fast shipping, bulk discounts, and expert support—all backed by years of filtration experience.
