How often you should replace your air filters could depend on the following:
- Air filter model
- Total indoor air quality
- Number of pets
- Household size
- Air pollution levels and construction around the house
For basic 1"–3" air filters, manufacturers usually tell you to replace them every 30–60 days. If you have from light to moderate allergies, you could get a better air filter or change them even more regularly.
Or, if you reside a more remote area or less occupied residence (like a vacation home) and there are not as many cars around, annually may 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 residence or one occupant and no pets or allergies: every 6–12 months
- Ordinary suburban house without pets: every 90 days
- One dog or cat: every 60 days
- More than one pet or if anyone has allergies: 20–45 days