How frequently you should change your air filters could depend on the following:
- Air filter type
- Overall indoor air quality
- Number of pets
- Household size
- Air pollution levels and construction around the home
For basic 1"–3" air filters, manufacturers often instruct you to change them every 30–60 days. If you have from light to moderate allergies, you could install a better air filter or change them even more regularly.
Or, if you live a more rural location or less occupied home (like a vacation residence) and there are a reduced number of cars around, each year might be frequent enough.
Here are averages that might help you decide how often you should get a new air filter at your residence:
- Vacation home 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