How often should HVAC filters be changed in a rental, and who is responsible?
Check filters monthly and clean or replace them as often as the manufacturer says, which is often every one to three months and more often in peak heating or cooling season. In a rental, put the responsibility in the lease: the tenant changes a simple filter and the landlord supplies it, or the landlord changes them all on a schedule. A written filter schedule is cheap and prevents a long list of problems.
How often a filter really needs changing
The U.S. Department of Energy's Energy Saver guide advises cleaning or replacing air conditioner filters monthly during peak use, or as the manufacturer recommends. The manufacturer's label or the unit manual is your starting point, since filter types differ.
| Situation | Check | Likely change |
|---|---|---|
| Standard 1 inch filter, cooling or heating season | Monthly | Every 1 to 3 months, per the manufacturer |
| Pets, smoking or dust in the unit | Monthly | Sooner than the label says if the filter looks gray |
| Thicker pleated or media filter | Every 3 months | As the manufacturer states, often longer |
| Vacant unit with HVAC off | At the turn | Replace at the turn so the next tenant starts clean |
The table gives a sensible rhythm, not a rule. The unit manual and the filter label control.
Who is responsible in a rental
There is no single national answer. Many leases make the tenant responsible for changing a simple filter and the landlord responsible for the equipment itself. Others leave it all to the landlord, especially in multifamily buildings with shared or hard-to-reach systems. Whatever you choose, say it in the lease and in the move-in packet.
- If the tenant changes filters, tell them the size, where it is, and how often. Supply the filters or a way to buy them.
- If you change them, schedule the visit, give the tenant notice of entry as your state requires, and record it.
- Either way, ask the tenant to report weak airflow, ice on the AC, or unusual noise at once.
Even if the lease puts filters on the tenant, the heating and cooling system is your property. Failing to maintain it can lead to repair bills, and in some places to a habitability issue if a unit has no working heat.
What a missed filter costs
A clogged filter restricts airflow, which makes the system work harder, and can lead to a frozen coil or an overheated furnace. That is an emergency visit in the first hot weekend or cold night. The filter itself is a few dollars.
Example a made-up building has 8 units. A pack of filters costs about $6 per unit, so a round of changes is $48. A weekend emergency call for a frozen AC coil in one unit is a made-up $240, five times the cost of changing every filter in the building.
A simple schedule that works
- Write the filter size on a label inside each unit's return or closet, and in your records.
- Pick fixed dates, for example the first of March, June, September and December, and give those dates to the tenant or to your maintenance person.
- On those dates, send a reminder to the tenant or schedule a short visit.
- Record each change with the date and, if you do it yourself, a photo of the old filter.
- At every turn, replace the filter regardless of schedule.
How DoorKeeping handles it
Ask Claude or ChatGPT to create a filter work order for each unit every quarter, and DoorKeeping can email the tenants a reminder with the filter size. When a vendor does the swap, send the job by link and keep the note on the property's record.
Sources
- U.S. Department of Energy: Energy Saver guide (air conditioner filters), read Oct 30, 2026
Questions
- How often should a landlord change the furnace filter?
- Check monthly and follow the manufacturer, which is often every one to three months. Change it at every turn.
- Can I make the tenant change the filter?
- In most places a lease can assign simple filter changes to the tenant. Say so clearly and supply the filter size.
- What happens if a tenant never changes it?
- Airflow drops and the system can fail. Check during your routine visits and send a written reminder before a problem starts.
- Do I need to change filters in a vacant unit?
- Replace it at the turn so the next tenant starts with a clean filter.