How regularly you should replace your air filters could depend on the following:
- Air filter model
- Total 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 install a better air filter or replace them even more frequently.
Or, if you live a more remote spot or less occupied home (like a vacation house) and there are not as many cars around, every year could be frequent enough.
Here are averages that might help you figure out how often you should get a new air filter at your residence:
- 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