How Often Should You Replace Your Air Filter?

In general, most air filter manufacturers and HVAC companies recommend changing your air filter every 90 days or 3 months. This may vary depending on the location of your home, if you have pets, and the age of your system and equipment. If you have pets in your house, it is advisable to change the filter every 60 days or 2 months. For households with multiple pets or people with allergies or respiratory conditions, we suggest changing the filter every 20 to 45 days.

Vacation homes or vacant homes that don't have much use should replace filters every 9-12 months. The more you use your home, the more often you need to change the air filter. An HVAC filter will only last one to three months on average. Therefore, it is important to keep track of the date you installed them.

If you wait too long to change the filter, indoor air quality will suffer. A general rule of thumb for pleated air filters (such as those manufactured by FilterBuy) is to replace the filter every 90 days. As the filter traps more dirt, dust and allergens from the air, its efficiency decreases. The Allergy and Asthma Foundation of America (AAFA) states that “indoor air quality is just as important as outdoor air quality”. A collapsed air filter can get stuck in the fan or create a large space, causing air to float around the filter without leaking out.

If you live in a “smaller house”, your air conditioners and ovens need to pump less air for the same amount of temperature change, which could mean fewer filter changes. To keep air quality under control and your home clean, you should replace the filter with a minimum interval of 2 to 3 months. If you have poor outdoor air quality or pets indoors, you'll need to replace your air filter more often. Some manufacturers recommend replacing air filters every 30 to 60 or 90 days, depending on the type of air filter. With air conditioners, replace the filter every 30 days with cheaper fiberglass filters to avoid higher energy bills. Not replacing the air filter accordingly can cause an increase in energy bills as clogged filters cause the system to work harder when air circulates.

It is important to note that there are high-efficiency filters that are designed to filter out small bacterial, mold, and fungal particles, but your standard MERV 8-11 filters will simply block out larger particles of dust, dirt & hair.