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18x20x1 Air Filter Merv 8
18x20x1 AC Filter Merv 11
18x20x1 Furnace Filter Merv 13
18x20x1 Filter Merv 13 Titanium
18x20x1 Filter Merv 10 Carbon
18x20x1 Filter Merv 8 Carbon 18x20x1 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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18x20x1 Air Filter

AC Furnace Air Filter 18x20x1 -Inches

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Product Description

Item Model Number: FKFB18X20
Brand: Filter King
Filter size: 18x20x1
Actual Size: 17.5 x 19.5 x .75
1-Inch Filter
MERV 8 Filter Rating
Protection From: Pollen, Dust, Mold, 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, 18x20x1 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.

18x20x1 Air Filter Reviews

What MERV Rating should I choose?

How Often to Change Your 18x20x1 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.

18x20x1 Air Filters Fit For A King (or Queen)

HVAC filters are necessary components to any system where incoming airflow cycles in your home. Airflow is often full of harmful microparticles irritants that cause discomfort and breathing problems for anyone inside the household. HVAC and furnace systems need 18x20x1 air filters as protection against the many airborne contaminants that try to enter the system. The filters act as cleansers, their tight mesh weave absorbing and trapping particles passing by in the airflow. As the particles become trapped, they begin to fill in the mesh and eventually cover the filter entirely. When the home air filter becomes too dirty, then it is important to remove it and use a new one to ensure fresh, clean air entering your home. When changing your air filter, never cut corners, always use the best air filters you can find. As our name suggests, we do not only guarantee royal and superior air filters, but we guarantee that your experience with us will be pleasant as well. 

18x20x1 Air Filter For Residential Use

The average home has biological and chemical pollutants, the amount of which depends on factors like pollution, season or place. Pollutants and allergens that float around may be the cause of breathing problems or allergic reactions or even the source of their development. The filters in a system prevent irritants from passing through, they do so until they are unable to absorb or trap any more contaminants such as pollen, fine dust, fumes, mold spores, and in some cases, virus carriers. 

A dirty filter is unable to adequately process airflow, leading to a distinct lack of fresh air throughout your home. The air conditioner in your home needs cycling or it begins to dry out and stagnate, and therefore reducing the air filter's efficiency and in turn causing lower indoor air quality. New air filters allow air to pass through without a problem, lowering complications and increasing the comfort of your home.

18x20x1 Air Filter Use for Apartments

Apartments have fewer options to bring in the fresh air, their smaller size also makes every breath of air that much more important. Air filters keep incoming air clean and cleanse out the airflow traveling throughout the system. In a home-like apartment, residents like smokers or pets become especially problematic. Smoke particles and pet dander have the tendency to float through your home and settle on any open surface they can when not filtered out through a system. Old filters are unable to properly process airflow, which means that the airborne particles build up and cause multiple complications in your home. New air filters keep the air flowing without a problem and provide protection to indoor air quality.

18x20x1 Furnace Filter

The heating and cooling systems in your home need air filters to prevent the incoming airflow from bringing in any irritants. The furnace system has the filters installed in between the heating area and the blower fan used to distribute the air. Heated air travels through the ducts and warms up your home, bringing heat without any intruding irritants. Like other air systems, furnace filters become dirtier over time and need regular maintenance to avoid problems with blocked airflow.

When regular filters are dirty, that leads to complications with air quality, furnace filters have the same problem but with additional dangers as well. Blocked furnace filters trap the heated air, which in turn cause the furnace to become increasingly hot. Temperatures build to an extreme degree, to the point where the furnace is severely damaged and the whole system is put at risk. Furnace filter maintenance prevents complications with blockages and keeps your home safe from mechanical failures.

Is It Time To Change Your 18x20x1 Air Filter?

While filter changing frequency depends on the manufacturer, most replaceable filters have a lifespan of between 60 and 90 days, and that’s when you should consider changing your air filter. 

Installing a new ac filter is a simple process, the owner’s manual for an air system often describes in detail where they need to go. Once found, the dirty filter should go into a sealed bag to avoid any of the particles from flying off. You are able to see the old filter’s size along its cardboard edge, allowing you to order a new standard or odd-sized filter.

MERV Rating 8, 11 & 13: Which Should You Use?

Air filter changing is a simple process, but one that is necessary to make sure that no complications affect the air systems. The replacement schedule is often dependent on the environment of your home and the efficiency of its 18x20x1 filters. Your home’s environment should tie into how often you purchase new filters, areas with more airborne irritants tend to clog filters at a faster rate. Indoor air particles also need to cycle out of your home, fresh airflow carries in the clean air while taking the old out.

A filter will capture and trap any and all the particles that it can out of passing airflow, their efficiency ranked in a measuring system. Your filter’s MERV rating simplifies its efficiency by ranking the filter on an easy-to-follow the scale. Filter King 18x20x1 air filters come with multiple MERV ratings available: 

Standard: MERV 8 Filter

MERV 8 filters are generally good at catching smaller particles between 3 - 10 microns, at an overall filtration efficiency of 85%. These filters are ideal for common household dust, pollen, mold spores, and other irritants.

Good: MERV 11 Filter

For homes with pets and people that suffer from mild allergies, MERV 11 filter can provide sufficient filtration to filter out pet dander, allergens and dust mites, in addition to what MERV 8 filters can achieve. 

Better: MERV 13 Filter

In addition to filtering everything that MERV 11 filters can do, MERV 13 air filters can filter out smoke, smog, bacteria, and virus carriers. MERV 13 provides the highest level of filtration and can filter up to 98% percent of airborne particles. It’s suitable for homes with people that smoke, have severe allergies, asthma, and other respiratory issues. 

Best: MERV 13 Filter (Titanium)

There is one thing that Filter King’s Titanium MERV 13 air filter does better than its MERV 13 standard filter - odor elimination. If you're having a severe and persistent household odor, then you may want to consider Filter King's highest-rated air filter. 

Furnace & AC Filter Delivery

Filter King offers professional subscription-based delivery services that have fresh, new 18x20x1 air filters delivered straight to your doorstep, on time every time. The air filters arrive at your home and are ready for immediate use in an air system. Air filters need consistent maintenance, and with our subscription service, you can have them delivered as often as on a monthly basis. We offer free shipping on 2 or more orders, which is one great deal among the many that we offer. Order today and receive your shipment as soon as in 2 days.