How frequently you should replace your air filters may 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 usually direct you to replace them every 30–60 days. If you suffer from light to moderate allergies, you could upgrade the air filter or replace them even more regularly.
Or, if you reside a more rural area or less occupied residence (like a vacation home) and there are not as many cars around, annually may be frequent enough.
Here are averages that may help you figure out how frequently you should get a new air filter at your residence:
- Vacation house or single occupant and no pets or allergies: every 6–12 months
- Common 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