RememberTheFilter.com

Custom Filter Builder

Pick your filter, depth, and size — we'll handle the rest.

Filter

Size

Review

Choose Your Filter & Depth

Select a filter on the left, then choose depth on the right.

Filter Type

Depth

Select a filter first.

⏳

Longer Lead TimeWashable aluminum filters are custom fabricated. Please allow extra production time.

Custom Size HVAC Filters | Any Dimension, 1/8″ Precision ⁽¹⁸⁾

Custom Size Air Filters — Built to Your Exact Dimensions

When standard 16x25x1, 20x25x1, or 20x20x4 sizes don't fit your system, we cut custom air filters to your exact specifications—down to 1/8″ on every dimension. Perfect for older homes, unusual HVAC cabinets, commercial rooftop units, and anywhere the right-sized filter isn't on the shelf.

What You'll Get

Any dimension, 1/8″ increments — width, height, and depth all cut to the exact size you specify
MERV 8, 11, and 13 options — match the filtration level you need, not just any size that fits
Pleated media construction — same durable frame and filter media we use on our standard residential and commercial lines
Typically built and shipped within a few business days — no overseas delays

How to Order a Custom Filter

Measure your filter slot. Width × Height × Depth. Measure the opening itself, not an existing filter that may be mis-sized.
Pick your MERV rating. MERV 8 for dust and pollen, MERV 11 for pets, MERV 13 for smoke and allergens.
Choose quantity. Singles for one-off needs, or bulk packs for subscription/commercial use.

Not sure how to measure? See our filter measurement guide or call 1-866-469-8556. Over 50 years of combined HVAC experience on our team—we'll help you get it right the first time.

Why RememberTheFilter.com for Custom Sizes

Exact Filters® — our proprietary custom-size line, built to spec
Filter Fit Guarantee — if the filter doesn't fit, we'll make it right
Free shipping over $50
Subscription available — auto-delivery on custom sizes, same as standard
Commercial pricing for property managers and facilities teams

⬇️ Additional Filters We Can Custom Make in Your Exact Size

We partner with the leading manufacturers in indoor air filtration to provide you with the highest-quality HVAC filters available. Whether you're looking to build a custom filter using our tool above or prefer to choose from our recommended options below, our knowledgeable customer service team is available anytime to help you find the perfect solution for your residential or commercial needs.

Highest Standards of Craftsmanship and Quality

We uphold stringent standards of craftsmanship and quality with our products. Choose from our range of custom furnace and HVAC filters, each meticulously made to your specified size for a perfect fit. Investing in a high-quality filter ensures cleaner, healthier indoor air for you and your family.

Benefits of Custom Size HVAC Filters

Enhanced Air Quality: Custom filters ensure a perfect fit, optimizing the air filtration process and enhancing indoor air quality.
Equipment Longevity: Properly fitted filters help maintain your HVAC system’s efficiency and longevity by preventing debris from entering the system.
Precision Fit: Custom filters are made to your exact specifications, ensuring no gaps or leaks that could compromise performance.
Versatility: Suitable for both residential and commercial HVAC systems, our custom filters cater to various needs.

Our Commitment to Customer Satisfaction

At RememberTheFilter.com, customer satisfaction is our top priority. We offer free shipping and our unique Filter Fit Guarantee. Should you make a measurement error while ordering your new filter, we'll remake your custom furnace filter or AC filter at no additional cost.

How to Order Your Custom Size HVAC Filter

Ordering your custom size HVAC filter is simple:

Measure Your Existing Filter: Accurately measure the dimensions of your current filter to ensure a perfect fit.
Select Your Specifications: Choose the type, size, and MERV rating that meets your needs.
Place Your Order: Use our easy-to-navigate website to place your order and enjoy free shipping.

Need Assistance? We're Here to Help!

If you need help with measurements or selecting the right filter, our customer service team is ready to assist. Give us a call at 1-866-469-8556 or reach out through our contact page.

Frequently Asked Questions About Custom HVAC Filters

We are here to help answer any questions you might have about ordering custom size HVAC filters.

Can I order a filter made to an exact size?

Yes! At RememberTheFilter.com, we specialize in custom air filters made to exact dimensions—not undercut, not rounded. Whether it’s 17-7/8 x 24-1/4 x 1” or something totally unique, we can make it.

What types of filters can be made in custom sizes?

We offer pleated filters, fiberglass panel filters, and even custom HEPA filters in made-to-order sizes. Available in MERV 8, 10, 11, 13, and beyond depending on the application.

How long does a custom order take to ship?

Most custom HVAC filters ship in 5–10 business days. All are made to order here in the U.S.

Are your custom filters made in the USA?

Yes. We only work with trusted U.S. manufacturers to ensure quality, airflow performance, and consistent sizing.

How do I measure for a custom HVAC filter?

Measure the exact length, width, and depth of the filter slot or old filter. We recommend rounding down to the nearest 1/8” for a snug fit.

Your Trusted Source For Filters

We offer a complete selection of high-performance HVAC filters. Whether you're replacing filters in your home, office, or commercial HVAC system, you'll find trusted options in MERV 1–13, including pleated, fiberglass, washable, and specialty filters.

All filters are made in the USA and sourced from leading manufacturers like AAF Flanders and Koch Filter. Choose from standard and custom sizes to ensure a proper fit for your system—and enjoy clean air backed by over 50 years of HVAC experience.

Never Compromise on Quality When It Comes to the Air You Breathe

Forced air systems, including furnaces, air conditioners, and heat pumps, circulate warm or cool air throughout your home via ducts and vents. These systems utilize filters to prevent dust and debris from being distributed along with the conditioned air. These filters not only enhance indoor air quality but also safeguard your forced air system.

When filters become overly clogged with particles, they diminish your system's efficiency, leading to increased heating and cooling costs, due to the hindered air movement from your heating system into your home or business. A severely clogged filter can cause a build-up of hot air near your heating system, triggering its emergency shut-off mechanism and leading to intermittent operation. Furthermore, clogged filters can exacerbate the presence of mold, dust, and other allergens in your home.

What MERV Rating Is Right for You?

MERV (Minimum Efficiency Reporting Value) measures how well an air filter captures particles. A higher number means better filtration—but it must still be compatible with your HVAC system. Here's a breakdown to help you choose the right filter for your home or business.

MERV 1–4

Basic protection. Captures larger particles like dust, lint, and pollen. Minimal airflow resistance. Best for older systems or basic residential use.

✔ Highest airflow
✘ Does not trap fine particles

MERV 8

Great balance of airflow and filtration. Captures mold spores, dust mites, pet dander, and pollen. Most common choice for residential HVAC systems.

✔ Good airflow
✔ Effective for everyday air quality needs

MERV 10

Enhanced dust-holding capacity and improved particle removal compared to MERV 8. Traps finer particles like mold spores, hair spray, and fabric fibers.

✔ More efficient than MERV 8
✔ Still maintains strong airflow

MERV 11

Captures smaller particles like auto emissions, smoke, and some airborne bacteria. Ideal for homes with pets or allergy concerns. Moderate impact on airflow.

✔ Great for allergies
✘ May reduce airflow in older systems

MERV 13

Highest residential-grade filtration. Captures airborne bacteria, tobacco smoke, and fine particles. Recommended for asthma, smoke exposure, or medical-grade needs.

✔ Best indoor air quality
✘ Not suitable for all systems without airflow evaluation

How to Measure HVAC Filters

To find the correct replacement, measure the length, width, and depth of your existing filter. Most filters are labeled with a nominal size (like 16x24x1), which is a rounded number—actual measurements are often slightly smaller. Accurate sizing ensures a proper fit and helps maintain airflow efficiency.

Step 1: Remove Old Filter

Turn off your system and remove the existing filter. Look for printed dimensions on the frame—this is usually the nominal size.

Step 2: Measure Actual Size

Use a tape measure to get exact dimensions (length × width × depth). Round down to the nearest 1/8" if needed—example: 15-5/8" × 23-5/8" × 3/4".

Step 3: Match or Order Custom

If your measurements don’t match a standard size, we offer custom filters made to your exact dimensions.

The perfect fit filter with custom made sizes.

Crafted with exact dimensions for a perfect fit, our filters effectively trap dust, pollen, and other indoor air pollutants, ensuring cleaner, healthier air in your surroundings.

Breathe Easier with Top-Quality Air Filters

Discover the ease of maintaining clean, healthy indoor air with RememberTheFilter.com. As a trusted provider of top-quality air filters since 2006, we offer a diverse range of products to meet all your residential and commercial needs. From custom furnace and AC filters to popular picks for forced air systems, we have it all. Plus, enjoy the benefits of free shipping, easy returns, and a user-friendly member portal for effortless subscription management. Choose RememberTheFilter.com for superior air filtration solutions and breathe easier in your home or business.

Our Top-Rated Filters: Proven Choices for Clean Air

With over 19 years of experience, RememberTheFilter.com has earned a reputation as a trusted source for premium air filtration products. We partner with leading brands to offer filters that consistently deliver top performance. Our best sellers are carefully curated based on customer feedback and real-world results, so you can be confident in their ability to enhance your air quality, improve system efficiency, and reduce dust and allergens.

Whether you’re maintaining your home, business, or facility, these top-rated filters are designed to meet your needs. We’re here to help you breathe easier, and our friendly team is always ready to answer questions or guide you to the perfect filter for your system.

Our product recommendations, best sellers, and other selections are based on the vast majority of typical HVAC systems. However, every system is unique, and many factors—such as specific system design, operating conditions, environment, and industry requirements—can influence performance and suitability. Please make sure that the products you choose are compatible with your unique system and needs.

We believe in providing not only top-quality products but also reliable, customer-focused service. Start with our best sellers for proven performance, and rest easy knowing you’re investing in filters trusted by countless customers nationwide. Your satisfaction is our priority, and we’re committed to ensuring every order meets your expectations.

RememberTheFilter.com for Premium HVAC Filters & Expert Service

With nearly 20 years online and over 50 years of combined HVAC filter experience, we’re more than just a retailer—we’re filtration experts. As a proud member of the National Air Filtration Association (NAFA), we serve residential, commercial, and government customers across the U.S. Our filters are made in America and sourced from leading manufacturers like AAF Flanders, Koch Filter, and more.

We believe in clean air, fair prices, and helping people—not algorithms.

✅ Nearly 20 years online helping homeowners and businesses nationwide
✅ 50+ years of combined HVAC filtration experience
✅ Member of NAFA – National Air Filtration Association
✅ Made in the USA – filters from AAF Flanders, Koch, and more
✅ Exact Filters® – custom built to your specs, down to 1/8"
✅ Trusted by schools, clinics, and commercial buildings across the U.S.

Filter Fit Guarantee™
Have concerns about ordering filters online? Your purchase is backed by our Filter Fit Guarantee™.
Free Delivery
We will ship your filters direct to your door, for free! All orders in the domestic U.S over $50.
Real Human Service
In America and we answer the phone. Call us at 1-866-469-8556.
Price Match
Find a better price on the same filter? Let us know, we will beat it!