How frequently you should replace your air filters could 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 usually direct you to install new ones every 30–60 days. If you have from light to moderate allergies, you could get a better air filter or get new ones even more frequently.
Or, if you live a more remote location or less occupied home (like a vacation house) and there are a reduced number of cars around, every year might be frequent enough.
Here are averages that might help you figure out how often you should get a new air filter at your house:
- Vacation residence or lone occupant and no pets or allergies: every 6–12 months
- Average 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