Change your HVAC air filter every 1 to 3 months — every month for 1-inch filters in homes with pets or allergies, every 3 months for 4-inch or 5-inch media filters in standard households. Check the filter monthly regardless; replace it whenever it looks visibly dirty.

Recommended change interval

  • 1-inch filter, pets, allergies — Every month
  • 1-inch filter, standard home — Every 2 months
  • 4-inch media filter — Every 6 months
  • 5-inch media filter — Every 6–12 months
  • HEPA bypass — Every 12 months
  • Always check monthly in dusty conditions

A clogged filter is the #1 cause of HVAC failure we see. Stay on schedule, or join the Mainstream Maintenance Plan for filter reminders.