Actual Size: 17.5x21.5x3.75"

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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.
Get the best air filter for your home’s unique needs today. Filterbuy high-quality air filters 18x22x4 keep your HVAC running efficiently. We design premium furnaces and HVAC air filters that are capable of trapping dust, allergens and pollutants. Such filters not only improve indoor air quality but also prolong the life of your heating and cooling equipment. Check out our premium filters which are rated top and expertly selected for your perfect fit and performance.
An 18x22x4 air filter measures 18 inches wide by 22 inches tall by 4 inches deep, a common size for residential HVAC and furnace systems that need stronger filtration than a standard 1-inch filter can deliver. The extra 4-inch depth means more pleated surface area, which traps more dust, pollen, pet dander, and allergens without choking your airflow.
Quick facts to know:
Best MERV rating: MERV 8 for everyday dust, MERV 11 for pet dander and pollen, MERV 13 for smoke, smog, and bacteria.
Replace every: 2–3 months (sooner with pets, allergies, or heavy use).
Why 4 inches: Lasts up to 3x longer than 1-inch filters and reduces strain on your HVAC system.
What to look for: Pleated, electrostatic media with a sturdy beverage-board frame — not flimsy fiberglass.
Pro tip: Always confirm your system is built for a 4-inch filter housing before upgrading.
Filterbuy's 18x22x4 pleated filters are made in the USA, ship free and fast, and come in MERV 8, 11, and 13 — with an auto-delivery option so you never have to remember when it's time to swap.
The best air conditioner filter 18x22x4 enhances air quality as well as system efficiency.
Filters of good quality eliminate allergens, dust and irritants.
Changing the filter regularly can increase the HVAC efficiency by 15%.
The finest MERV filters have the ability to capture as much as 98% of microscopic particles in the air.
Filterbuy offers trusted and durable filters with fast shipping.
Selecting the perfect 18x22x4 HVAC filter will result in clean air that does not overwork the HVAC system. This size is prevalent in plenty of households and gives a decent balance between airflow and filtration. Filterbuy provides quality filters that can take in dust, pollen, pet dander, and other particles. They are the protection for both your air and your equipment.
You will have the option of pleated filters with MERV ratings of 8, 11, or 13. The regular swapping of your filter will help in preventing the accumulation of dirt, improving airflow, and thus decreasing the load on your HVAC system. This also lowers energy and repair costs. Filterbuy filters are easy to install and built to last.
Order today for cleaner air and a healthier home.
Superior Efficiency - Our pleated air filters are at least 20 times more efficient than standard fiberglass filters at capturing dust, allergens and bacteria.
High-Strength Frame - They feature a robust beverage board frame designed to handle humidity and temperatures up to 200∘ F without warping or weakening.
Advanced Filtration Media - We use a special synthetic electrostatic media that is significantly more efficient at capturing particles compared to the basic cotton media found in other filters.
Indoor air is 2 to 5 times more polluted than outdoor air says the EPA.
Using the right 18x22x4 filters helps reduce dust and allergens noticeably.
Source: EPA - Indoor Air Quality
The DOE reports that replacing air filters on time improves HVAC efficiency by up to 15%.
Clean and quality filters lower energy costs and reduce HVAC wear.
Source: DOE - Heating and Cooling
AAFA reports that MERV 8 and above filters eliminate up to 98% of airborne particles
People with allergies or asthma are suited as better indoor air quality is provided.
Source: AAFA - Indoor Allergens

Getting the right 18x22x4 HVAC and furnace air filter for allergies goes far beyond regular maintenance—it stands for healthier air and a more efficient system.
Better Air, Less Dust
Homeowners report reduced allergy symptoms and cleaner surfaces after switching to this filter.
Longer HVAC Life
The existence of a good filter signifies less use of your HVAC unit, thus punctuating less number of repairs and lower electricity bills.
Healthier Living
Fresher air is conducive to increased health and comfort for the occupants of that house.
Take the measurements of your existing filter to ensure that it is proper and exact.
Consider your air quality needs, take note of allergies, pets or pollution before making any decision.
Browse Filterbuy.com selection of top-quality filters.
Order online for great prices and fast shipping.
Setup your new filter.
Take out your new air filters from Filterbuy packaging.
Detach the old filter.
Verify system compatibility with the filter.
Start experiencing better air quality in your environment.
Replace filters every 2–3 months based on usage.
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.

The numbers represent the filter’s dimensions: 18 inches by 22 inches by 4 inches thick. This size fits many residential HVAC and furnace systems, ensuring proper airflow and filtration.
It depends on your home environment and filter type, but generally every 1 to 3 months. Homes with pets or allergy sufferers may need more frequent changes for optimal air quality.
Minimum Efficiency Reporting Value rates a filter’s ability to trap particles. For most homes a MERV rating between 8 and 13 offers a good balance of filtration and airflow. Higher ratings provide better filtration but may restrict airflow if your HVAC isn’t designed for it.
Not all filters are created equal. Choose high quality filters designed for your HVAC’s specifications to avoid airflow issues and ensure effective pollutant removal. Always verify compatibility before purchasing.
Filterbuy offers a wide selection of trusted, durable 18x22x4 air filters with expert guidance and fast shipping, making it easy to find the right filter for your home.
Choose the correct size
Turn off the power supply
Remove the old air filter
Dispose the old product
Insert the best 18 x 22 x 4 air filter from Filterbuy
Replace the cover
Buy 18x22x4 air filter in bulk
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 18x22x4 air filter and offer direct shipping.
Using a cheap 18x22x4 fiberglass air filter might save you a little money upfront. But cheap filters don’t last long or clean the air well. A high-quality 18x22x4 electrostatic air filter with the right MERV rating protects your unit and your health.
Yes. An 18x22x4 carbon air filter is the same as an 18x22x4 charcoal air filter. They’re the best at improving your home’s air quality and keeping unpleasant odors away.
Choose 18x22x4 air filter MERV 8 when dust is your primary concern.
Choose 18x22x4 air filter MERV 11 when you’re sensitive to pollen and dander.
Choose 18x22x4 air filter MERV 13 when smog, smoke and bacteria are top concerns.
Order your perfect-fit 18x22x4 HVAC and furnace air filter today and start breathing cleaner, healthier air at home. Pick your MERV rating, set up auto-delivery, and let Filterbuy ship your American-made filters straight to your door — fast and free.