How often you should change your air filters can depend on the following:
- Air filter model
- Complete indoor air quality
- Number of pets
- Household size
- Air pollution levels and construction around the home
For basic 1"–3" air filters, manufacturers usually instruct you to change them every 30–60 days. If you suffer from light to moderate allergies, you could get a better air filter or replace them even more frequently.
Or, if you reside a more remote spot or less occupied residence (like a vacation house) and there are a reduced number of cars around, yearly might be regular enough.
Here are averages that might help you decide how often you should get a new air filter at your house:
- Vacation residence or lone occupant and no pets or allergies: every 6–12 months
- Average suburban home without pets: every 90 days
- One dog or cat: every 60 days
- More than one pet or if anyone has allergies: 20–45 days