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18x18x1 Air Filter Merv 8
18x18x1 AC Filter Merv 11
18x18x1 Furnace Filter Merv 13
18x18x1 Filter Merv 13 Titanium
18x18x1 Filter Merv 10 Carbon
18x18x1 Filter Merv 8 Carbon 18x18x1 Filter Merv 8 Carbon
Protects All Against
  • Pollen protection
  • Dust protection
  • Mold protection
  • Dust Mites protection
    Dust Mites
  • Bacteria protection
  • Pet Dander protection
    Pet Dander
  • Smoke protection
  • Viruses protection
  • Cooking Smoke protection
  • Odor protection
  • Smog protection
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18x18x1 Air Filter

AC Furnace Air Filter 18x18x1 -Inches

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Product Description

Item Model Number: FKFB18X18
Brand: Filter King
Filter size: 18x18x1
Actual Size: 17.5 x 17.5 x .75
1-Inch Filter
MERV 8 Filter Rating
Protection From: Pollen, Household Dust, Mold Spores, Dust Mites, Bacteria, Pet Dander, Smoke, Viruses
Residential / Commercial Use

Manufactured in the US

Why Buy Air Filters From Filter King?


In comparison to fiberglass filters, 18x18x1 pleated air filters are at least 20 times more effective. All Filter King air filters are made in the US.


Filters frames are made out of heat resistant paperboard with horizontal grid supports. Able to withstand temperatures of up to 200° F and resistant to moisture, the paperboard frames do not support microbial growth and outperforms traditional cardboard frames.


Chemical free, electrostatically charged synthetic polyester media is pleated, maximizing the surface area, to capture a high number of airborne particles as small as 0.3 microns with low air flow resistance. To increase durability, the media is supported with a corrosion resistant steel wire.

18x18x1 Air Filter Reviews

What MERV Rating should I choose?

How Often to Change Your 18x18x1 Air Filter?

Filter King AC & furnace filters aren’t the typical fiberglass filters that need to be replaced every 30 days. Our filters can typically be used for 3 to 5 months before requiring to be changed. Naturally, a variety of things influence filter lifespan.

Some of the factors that influence your filter’s life include outdoor air quality, whether pets are in the home, and how well your HVAC system is maintained.

Your air filter becomes clogged over time by trapped particles, preventing airflow. The efficiency of the HVAC filter declines. Your system must work harder to heat and cool your home. The extra strain on the HVAC system causes higher energy bills. Regular home air filter replacements can prevent expensive system repairs or replacements down the road.

You should change your filter more frequently if you notice:

  • Household dust build-up
  • The air isn’t cooling as is used to
  • There’s more dust near the air vents
  • A dirty filter surface
  • Higher energy bills
  • Burning smells near your HVAC system.

18x18x1 Air Filter

Your air systems work at a constant rate to bring in proper air flow and deliver that fresh, clean smell inside your home. Your 18x18x1 air filters will clean out passing airflow so that your ducts are free of any intruding irritants. Air filters are necessary to your home, without filtration there is no way to fully understand just what kind of irritants are floating into your home. Your air filters keep the irritants out, but they can only protect your home air conditioner systems for a finite amount of time before they need maintenance. Air filters need periodic replacement on a regular schedule or the resulting complications will begin to affect your home.

18x18x1 Air Filter Use for Residential Homes

A residential home is not always able to ensure clean indoor air by just opening a window or simply relying on the air conditioner system. The air quality outside of your home may contain high levels of pollutants or allergens that could cause some severe breathing issues. When your home suffers from low air quality, then the result is an uncomfortable and possibly unsafe, atmosphere that has residents watching what they breathe. Your 18x18x1 air filters are able to prevent any dip in indoor air quality, but in the process become dirty themselves and require maintenance. Dirty air filters are able to continue protecting your home against irritants but they also block air flow, causing a different set of problems entirely.

When your air filters create a blockage in your HVAC system, then the resulting lack of air flow leads to problems throughout your home. The inside the air throughout the various rooms in your home need to cycle out, continuous replacement prevents stagnation. When air cycling stops, and the air is not replaced, then the old air begins to stagnate and dry out. Old and dry air is unhealthy for the lungs, and over time it may cause home residents to start developing breathing problems.

Filter Use for Apartments

The average apartment has fewer options to endure airflow, air systems provide the bulk of clean air which means filtrations are that much more important. The airflow needs cleaning to avoid irritants from contaminating your home and causing breathing issues. However, irritants are also able to come from the inside of your home as well, especially for homes with resident smokers or pets. The irritants that fill your home’s air need to cycle out of its rooms via airflow without issue, or the particles begin to build up.

Dirty air filters stop the air in your home from flowing, from room to room, and eventually back outside. When the cycle stops, the result leads to more than stagnation, the airborne particles in a room remain as well. Lingering irritants have the tendency to cling to any open surfaces that they are able to find. your home becomes much less comfortable when its becomes covered in a layer of grime or household dust, which make cleaning much harder and air less breathable.

18x18x1 Furnace Filter

Your air filters are able to fit HVAC, heating, and cooling air systems alike in order to ensure clean and healthy airflow. The Filter King 18x18x1 air filters are able to fit in appropriately sized furnace systems to provide a layer of protection. Your furnace filter fits in between the part of the furnace that heats the air and the blower fan which distributes it. Like in other air systems, the furnace filter will inevitably become dirty and incapable of processing airflow. Unlike other air systems, a dirty filter may cause more severe issues that border on the danger to your home.

The airflow in a furnace becomes warmed by extreme heat that regulates the temperature to match your thermostat. When the airflow becomes blocked, this heated air is unable to enter your ducts to warm the home, causing temperature fluctuations. The trapped air is also dangerous, causing a spike in heat the system may not be able to handle. An overheated furnace is in danger of having its parts damaged, which is very costly and time consuming to fix. A new 18x18x1 filter will help you avoid certain complications and keep the heated air flowing without incident.

18x18x1 Filter Changing Practices

Old air filters need replacement before any complications begin to become more obvious over time. Certain problems are easily noticed, like air stagnation or heating problems with an HVAC system. Other issues only become evident over time, such as the increased billing a dirty air filter creates as the air systems need to work harder eventually using more energy to try and bypass it. HVAC system's increased use of energy resulting in greater energy costs also causes faster wear down on its components, requiring costly replacements over time.

You will be able to gauge how often your air filters need maintenance at a more accurate level by taking environment and MERV ratings into account. The environment of your home determines the amount of household dust, debris, pet dander, pollutants, or mold spores that your air filter will need to cleanse out of air flow. Your filter’s MERV (Minimum Efficiency Reporting Value) rating determines just how efficient your air filter is at cleansing out passing air flow. Our 18x18x1 size air filter ranks as an 8,11 or 13 on the MERV scale, providing protection against irritants like:

  • Pollen
  • Household Dust
  • Mold Spores
  • Dust Mites
  • Bacteria
  • Pet Dander
  • Smoke
  • Virus’s

Replacing an Old Air Filter

A new air filter should go into the various air systems around the house as often as monthly, depending on different factors, to avoid complications. You can see the size of the filter you need by finding the old filter and reading its sizing off of its cardboard edge. A 18x18x1 size filters are available from Filter King and are usable as soon as they arrive at your front door. The installation process is usually detailed more thoroughly in an HVAC system owner’s manual.

Air Filter Delivery

Filter King offers a full range of filter types and sizes, including effective 18x18x1 size filters ready for use upon arrival. Our premium folders are easy to order, easy to install, and affordable to the average household. Good news for those who prefer having extra filters at their disposal. The more filters per order, the larger the discount you will receive per order. We even offer free shipping for your filters if you order more than one filter, making it easier than ever to ensure that your home air remains clean and fresh smelling!