How regularly you should change your air filters might depend on the following:
- Air filter type
- Total indoor air quality
- Number of pets
- Household size
- Air pollution levels and construction around the residence
For basic 1"–3" air filters, manufacturers often instruct you to get new ones every 30–60 days. If you have from light to moderate allergies, you could upgrade the air filter or get new ones even more regularly.
Or, if you live a more country area or less occupied residence (like a vacation house) and there are not as many cars around, annually might be regular enough.
Here are averages that could help you figure out how regularly you should get a new air filter at your house:
- Vacation house or single occupant and no pets or allergies: every 6–12 months
- Common suburban residence without pets: every 90 days
- One dog or cat: every 60 days
- More than one pet or if anyone has allergies: 20–45 days