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0.5 Inch Air Filters

At Filter King, we manufacture a diverse range of 0.5 inch air filters. You never have to worry about getting the wrong size filter, since our products are backed by a 30-day guarantee. Select the furnace filter you need below.

Available 0.5 Inch Air Filters

Can’t find your 0.5 inch air filter? Click here for Custom Air Filters

Are 0.5 Inch Air Filters Right for Me?

The majority of air filters are only one inch thick. However, there are systems that can easily accommodate 0.5 inch air filters. Generally speaking, the thicker it is, the better it works to capture airborne particles and protect your HVAC system from dust, dirt, and debris. Thicker filters also mean you can go longer between replacement filters.

You’ll need to look at your current filter to see if your system will fit the 0.5 inch air filter thickness. Some air filters will have the dimensions printed on the side. If not, measure the longest side, then the shorter side, and the thickness. Look inside to determine if the opening will hold a larger one (if you’re using a 1 inch now.)

Your measurement will be the actual size. When shopping, use the nominal size - the actual size, rounded up the nearest whole inch.

What Filter Rating is Ideal?

When shopping for HVAC filters for your home or office, you’ll find a variety of rating options. Ideally, you should be following the Minimum Efficiency Reporting Value (MERV) rating scale. This is the only consumer standard rating system. It was developed by the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) to help homeowners.

Any filters with a MERV rating, regardless of type or brand, will provide the same level of filtration as any other product with the same MERV rating. The higher MERV rating, the more contaminants it removes from the air.

Other rating systems are proprietary and not consistent across brands and types. You may also see MPR, or microparticle rating (a system created by 3M) or filter performance rating (FPR). The FPR is exclusive to Home Depot stores.

MERV ratings run from 1 to 20. The filters recommended for use in your home’s AC or furnace fall between MERV 8 and MERV 13. For those without pets or breathing issues, a MERV 8 provides enough filtration. They protect against pollen, dust, lint, dirt, mold spores, and smog.

For pet owners, a MERV 11 provides better filtration. It removes additional airborne particles, including pet dander.

For those with asthma, severe allergies, or other health conditions affecting the lungs, the MERV 13 is the highest level of filtration recommended for residential use. It filters smoke, some types of bacteria and viruses, and more.

MERV 14 and higher is only recommended for healthcare and other areas where the cleanest air possible is required. Using them in your residential system will only cause the system to work harder than necessary.

How Often Do I Need to Change My Air Filter?

You can expect to go between three to five months before you need to change it. Check it monthly to make sure it’s still clean. Dirty filters block airflow, which makes your system work harder. This increases your energy bills and wears the HVAC out faster.

Keep Your Air Clean With Our Subscription Service

If you don’t want the hassle of remembering when it’s time to change the filter, sign up for our free reminder service. Want to make sure you always have a clean one on hand when you need it? Subscribe to our delivery service. Choose the products you need, and how often you want them to be delivered. We take care of the rest.

Questions about air filter sizes?


  • Are 0.5 inch filters better than 1 inch filters?

    Thicker air filters work better and last longer than thin air filters. In our tests, we found that the thicker the filter, the better it works and the longer the replacement intervals. That means it's better for you and for your heating, ventilating, and air conditioning (HVAC) system.

  • Do all HVAC systems have 0.5 inch filters?

    Not all HVAC systems have 0.5 inch filters. Some have different sizes, with one inch filters being the most common. It's best to check your system's manual or contact the manufacturer. Additionally, you can remove the current filter and measure its depth. I will likely measure 1, 2, 4, or 5 inches.

  • Can I use a 0.5 inch filter?

    Yes, you can use a 0.5 inch air filter if your HVAC system is designed for a 0.5 inch filter. Not all homes will accommodate 0.5 inch furnace filters, so if your system uses any other thickness, then a two inch air filter would not be recommended.

  • Can I stack two 0.5 inch filters together?

    Multiple smaller filters will not fit in one slot, and if they do, it could create costly damage to your AC unit. It is best to not stack filters together at all, and if you have a larger filter slot, use the largest filter that you can. The worst case scenario of trying to stack two 0.5 inch air filters together into a 5-inch filter that’s too tall for the housing. That would require modifying the housing or replacing it altogether.