How often you should change your air filters could depend on the following:
- Air filter kind
- 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 direct 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 reside a more country area or less occupied residence (like a vacation house) and there are a reduced number of cars around, each year may be often enough.
Here are averages that might help you decide how frequently you should get a new air filter at your residence:
- Vacation residence or one occupant and no pets or allergies: every 6–12 months
- Ordinary suburban home without pets: every 90 days
- One dog or cat: every 60 days
- More than one pet or if anyone has allergies: 20–45 days