How frequently 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 typically instruct you to change them every 30–60 days. If you deal with from light to moderate allergies, you could install a better air filter or change them even more regularly.
Or, if you're in a more rural area or less occupied home (like a vacation residence) and there are a reduced number of cars around, every year may be frequent enough.
Here are averages that may help you decide how often you should get a new air filter at your residence:
- Vacation residence 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