How often should you clean air ducts?
Updated July 2026
Have your air ducts professionally cleaned every 3 to 5 years, and only if you have a real reason, because for most homes duct cleaning is not an annual chore. The trade group NADCA suggests that interval, with earlier cleanings warranted after a renovation, a pest infestation, or visible mold. Routine dust settling in the ducts of an ordinary, well-filtered home does not meaningfully hurt airflow or the air you breathe.
What changes the interval
| Your situation | Interval | Why |
|---|---|---|
| Typical home, no issues | Every 3-5 years, or skip | NADCA guidance; most homes never truly need it |
| Just finished a renovation | Clean once, after the cleanup | Drywall dust and debris load the whole duct run |
| Visible mold on registers or in ducts | Clean now, then find the moisture | Mold is a real reason, but it returns unless the cause is fixed |
| Rodent or insect infestation | Clean and sanitize | Droppings and nests in ducts are a genuine air-quality issue |
| Salesperson pushing a $79 special | Decline | Blow-and-go crews without a HEPA vacuum just stir dust around |
The cost of skipping it
Where the money goes: a legitimate cleaning that uses a truck-mounted HEPA vacuum and mechanical agitation runs $450-1,000 for an average 1,500-2,500 sq ft home, and it genuinely helps after construction dust, rodents, or mold. The trap is the $79 "whole-house" coupon: those crews wave a shop vac around, upsell hard, and can knock debris loose without capturing it. If the ducts are not actually dirty, the best value is to spend nothing and keep changing filters on schedule.
How to do it (Pro job $450-1,000 · every 3-5 years)
- Pull a register cover and look inside with a flashlight; a light film of dust is normal and not a reason to clean.
- Clean only for cause: post-renovation debris, clear signs of rodents or insects, or visible mold growth.
- Hire NADCA-certified companies that use a HEPA-filtered vacuum and mechanical agitation, not a bare shop vac.
- Fix the moisture source before cleaning any mold, or it simply grows back within months.
- Get the full scope and price in writing, and decline on-site "you also need" upsells for coils, sanitizer, or blowers.
Knowing the interval is the easy half. OnOtto reminds you at the right interval, and it won't let you snooze it into next year. Tasks persist until they're done, and completing duct cleanings schedules the next one automatically.
Put this on autopilot, free for 30 daysFrequently asked questions
Does duct cleaning improve allergies or air quality?
For a typical home, the evidence is thin. The US EPA has long said routine duct cleaning has not been shown to prevent health problems or measurably improve air quality in ordinary conditions. A good filter, changed on schedule, does far more for the air you breathe. Cleaning earns its keep in specific situations, after mold, vermin, or heavy construction dust, not as a standing allergy remedy.
Is the $79 duct cleaning deal a scam?
Usually it is bait-and-switch. The rock-bottom coupon gets a crew in the door, then the price climbs with per-vent fees, "mandatory" sanitizer, and register add-ons, often landing near the $450-1,000 a real cleaning costs anyway, but done with a shop vac instead of proper HEPA equipment. If you have a genuine reason to clean, hire a NADCA-certified company on a written quote and ignore the too-cheap-to-be-real ads.
How often should I inspect ducts versus clean them?
These are different jobs. A quick visual inspection every couple of years is worth doing to catch disconnected joints, crushed flex runs, and leaks that waste conditioned air, and it is free to eyeball accessible sections yourself. Full cleaning, by contrast, is a once-every-few-years or for-cause event. Keep the inspection on your regular maintenance checklist and reserve the paid cleaning for when there is real dirt, mold, or debris.