Actual Size: 16.00x21.50x1.75"
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: 16.00x21.50x1.75"
Free Delivery Factory-Direct Low Prices, Made in the USAHassle-Free Returns & Free ExchangesRESIDENTIAL AND/OR COMMERCIAL USE
Change Every 3 Months
Actual Size: 16.00x21.50x1.75"
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: 16.00x21.50x1.75" in → 16x21.5x2 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 | 16 x 21.5 x 2 inches |
| Actual Size | 16.00 x 21.50 x 1.75" 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 |
Written by Michelle Wan. Reviewed for technical accuracy by David Clark, Licensed HVAC Technician. Published: August 12, 2026. Updated: August 12, 2026
A 16x21.5x2 MERV 11 air filter is a 2-inch-deep pleated filter, cut to an actual size of 16.00 x 21.50 x 1.75 inches. MERV 11 is our Superior tier, made for allergy sufferers and the homes that deal with pets and pollen, and it captures 95% of airborne particles. Filterbuy cuts, pleats and frames every one to order in our own US plants. Fast and free 2-day delivery to most US states, from $14.66 per filter in bulk packs.
The actual cut size is 16.00 x 21.50 x 1.75 inches. Order by the nominal name, 16x21.5x2.
MERV 11 captures 95% of airborne particles, which is the Superior tier and the one built for allergy sufferers, pets and pollen.
A 2-inch filter holds roughly twice the pleated media of a 1-inch filter of the same face size, so it keeps working for a full 90 days.
16x21.5x2 is a half-inch nominal size, so most hardware stores won't have it on the shelf. It's a size you order.
Filterbuy's 16x21.5x2 MERV 11 filters drop from $31.99 for one to $14.66 each in 12-packs, a 54% per-filter savings.
Finding your size is the easy part. Pull the old filter out and read the frame: the big number printed on the edge is the nominal size, and that's the one you order by. If it says 16x21.5x2, you're done. No old filter to read? Measure the slot it goes into, length then width then depth, and round each up to the nearest half inch.
The nominal size and the measured size aren't identical, and that's deliberate. Nominal is the ordering name. The actual cut runs a little smaller so the filter slides in without binding, and on this one that clearance is in the depth: 1.75 inches for a slot called 2 inches. After a decade of manufacturing at Filterbuy, the ordering mistake we see most is measuring two sides instead of three. Our guide to measuring your air filter walks you through it in about two minutes.
Half-inch sizes like this one rarely make it onto a store shelf, which is why people reach for a 16x22x1 and hope it's close enough. It isn't. That filter measures 15.50 x 21.50 x 0.75 inches, so it's half an inch short and an inch shallower, and the matching width is what makes it feel right in your hands. If the size you need isn't listed at all, build a custom air filter cut to the eighth of an inch.
Check where the filter lives before you check the size. If yours slides in behind a wall or ceiling return grille, it's almost certainly a 1-inch filter, because grille racks are rarely built deeper. A 2-inch filter usually means a slot in the blower cabinet or the return duct, where the extra depth fits.
So measure the rack depth first. If it comes back at 1 inch, take the 16x21.5x1 in MERV 11 instead. A 2-inch filter won't seat in a 1-inch rack, and stacking two 1-inch filters isn't a substitute either. Our guide to common furnace filter size problems covers the rest.
MERV 11 captures 95% of airborne particles. MERV, short for Minimum Efficiency Reporting Value, is the industry scale for how much a filter takes out of the air, and 11 sits in the middle of the three ratings we make for homes. Here is how the three compare:
MPR and FPR are third-party rating systems and are not Filterbuy ratings. Check your HVAC manual to confirm which MERV rating your system is set up for, the same way you confirm a size.
Check your HVAC manual to confirm which MERV rating your system is set up for. It's a quick fit check, the same as confirming a size, and one line in the manual usually settles it.
Pick the tier by what's in your air. MERV 8 is the standard choice for most homes and captures 90% of airborne particles. MERV 11, this page, is the Superior tier for allergy sufferers, pets and pollen. MERV 13 is our Optimal tier, the one to choose for smoke, and it captures 98% of airborne particles. If odors are what you notice most, our Odor Eliminator carbon filters are built for that instead.
A 2-inch filter carries roughly twice the pleated media of a 1-inch filter with the same face dimensions. More media means more surface to hold what it catches, and that's why we rate this one for a full 90 days. We build each filter with electrostatically charged media, meaning the fibers carry a light static charge that helps them hold fine particles. An aluminum dual-wire backing keeps the pleats from sagging, and the frame resists moisture, so it won't warp in a humid attic.
Three federal figures explain why this matters:
Americans spend about 90% of their time indoors. Indoor levels of some pollutants run 2 to 5 times higher than outdoors.
Why it matters: your filter handles the air you breathe most.
Source: U.S. EPA, Report on the Environment
One in four U.S. adults has a seasonal allergy. 25.2% were diagnosed in 2024.
Why it matters: MERV 11 is the tier we build for allergy sufferers.
Source: CDC / NCHS Data Brief 545, January 2026
Heating and cooling use nearly half of home energy. ENERGY STAR says change filters at least every 3 months.
Why it matters: a fresh filter is the cheapest maintenance on the list.
Source: ENERGY STAR (U.S. EPA)
Filterbuy sells this size factory-direct, so the per-filter price drops with quantity:
Pricing shown for the 16x21.5x2 MERV 11 pleated air filter and verified on the date of publication. Shipping is free on every order. Auto-delivery takes an additional 5% off.
We've done the yearly math for you. On a 90-day schedule, a 4-pack at $17.74 each runs about $71 for the year. Change every 60 days for pets or allergies and you'll need six, which at $15.99 each is about $96. Auto-delivery takes another 5% off either number and remembers the date so you don't have to.
It's cut to 16.00 x 21.50 x 1.75 inches. Order it by the nominal name, 16x21.5x2, which is the number printed large on the frame.
MERV 11 is our Superior tier, built for allergy sufferers, and it captures 95% of airborne particles. It's the tier we point pet owners toward too. If anyone in your home has a medical question about their symptoms, that's one for their doctor rather than a filter label.
Every 90 days in a typical home, every 60 with pets or allergies, every 30 if you're somewhere smoky. Want to check between changes? Hold the filter against a sheet of white paper. If it's gone grey, swap it. Our air filter basics library has more.
Your HVAC brand doesn't set your filter size. The slot does, and two homes with the same model can take different filters depending on the ductwork. Measure the opening rather than shopping by brand, then check your manual for the MERV rating your system is set up for.
Filterbuy sells it direct at filterbuy.com in packs from 1 to 12 or more, with fast and free 2-day delivery to most US states. Most hardware stores don't stock half-inch nominal sizes. We're a manufacturer rather than a reseller, so every filter is cut, pleated and framed to order in our own US plants.
MERV: Minimum Efficiency Reporting Value, the industry scale for how much a filter takes out of the air. Higher numbers capture more.
Nominal size: The ordering name printed on the filter frame, such as 16x21.5x2.
Actual size: The cut size of the filter, such as 16.00 x 21.50 x 1.75 inches.
Pleated media: Filter material folded into ridges so there is more surface to catch what passes through.
Electrostatically charged media: Filter fibers carrying a light static charge that helps them hold fine particles.
MPR and FPR: Third-party rating systems from other companies, not Filterbuy ratings. MERV 11 compares to MPR 1000-1200 and FPR 7.
