Buying Guide

How Often You Should Change Your Air Filter

When to Change an Air FIlter
a man replacing an air filter inside the home
  • The frequency at which your air filter should be changed depends on a variety of factors, including the type of filter in your HVAC unit.
  • Fiberglass filters are a lower cost option, but they need to be disposed of and replaced roughly every 30 days.
  • Pleated air filters are usually made of higher quality materials and can last anywhere from three to six months depending on the material, manufacturer and the frequency of use. 
  • Follow the instructions included with your filter for more detailed guidance on the recommended changing schedule.


Tip: Some models offer an air filter subscription. Have a new filter delivered every few months so you never forget to order a new one.

Variables that Affect Your Air Filter
a woman replacing an air filter inside the home

Many other factors contribute to the longevity of your air filter:

  • Home size. Larger homes circulate larger amounts of air which means the filter may need to be changed more frequently than those in smaller homes. 
  • Air quality. If you live in a bigger or busier city, the air in your home may be more polluted with excess smog, dust and debris. This can make your air filter work overtime, which means it will need to be changed more often.
  • Pets. Since common household pets can shed and track in dirt from outside, you’ll need to change the filter regularly to keep it clear of pet hair and dander.
  • Allergies or medical conditions. Homeowners with severe allergies, asthma or other respiratory conditions should consider changing the air filter more often than usual to prevent flare ups.