How regularly you should change your air filters can depend on the following:
- Air filter model
- Total indoor air quality
- Number of pets
- Household size
- Air pollution levels and construction around the residence
For basic 1"–3" air filters, manufacturers typically tell you to change them every 30–60 days. If you suffer from light to moderate allergies, you could install a better air filter or get new ones even more often.
Or, if you reside a more remote location or less occupied house (like a vacation home) and there are fewer cars around, every year might be frequent enough.
Here are averages that might help you know how frequently you should change the air filter at your house:
- Vacation residence 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