How long they actually last
Some fail at ten months. Some run for a decade. The difference is rarely luck.
Owner reports cluster around three to five years, and the spread either side is enormous. Some units fail before ten months. Others run past nine or ten years — but almost always with replaced batteries and brushes along the way.
The difference is rarely luck. It is maintenance and parts availability.
What actually fails, in order
- Battery — capacity degrades from around year two or three. Usually replaceable
- Brush motor — dies early if hair is left to wrap and strain it
- Side brushes — bend and stop spinning. Cheap, easy
- Sensors — dusty cliff sensors cause the machine to refuse to move or, worse, fall down stairs
- Wheels — hair wraps the axles and steering degrades
- Dock contacts — corrode or dirty, and the machine stops charging reliably
The maintenance that actually extends life
Owners with the longest-running machines describe the same routine, and it is short.
| How often | What |
|---|---|
| Weekly | Empty the bin (unless self-emptying). Clear hair from the main brush and side brushes |
| Monthly | Wipe the cliff sensors and camera lens with a dry cloth. Check wheel axles for wrapped hair |
| Every 2–3 months | Wash or replace the filter. A clogged filter reduces suction more than any spec difference |
| Every 6 months | Wipe the dock charging contacts. Check the brush for splits |
| Year 2–3 onward | Expect to replace the battery. Budget for it |
The monthly brush clean is the single highest-value item on that list. Long hair wrapped around a roller puts continuous strain on the brush motor, and brush motor failure is one of the most common ways these machines die.
Machines with available parts last years longer. Check spares before buying, not after something fails. See vacuum cleaners → Advertising — we may earn a commission.
Sensors deserve special mention
Cliff sensors are small infrared eyes on the underside that detect a drop. When they get dusty, two things can happen: the machine becomes over-cautious and refuses to cross dark flooring, or it stops detecting stairs correctly. Owners have reported units falling down stairs, including replacement units on their first run.
Wiping them with a dry cloth takes ten seconds and prevents both failure modes.
The buying decision this implies
Before purchase, search the model name plus "replacement battery" and "replacement brush". Two outcomes:
- Parts available and reasonably priced — this machine can realistically last five-plus years
- No parts, or only through the manufacturer at high cost — this is a three-year machine whatever the reviews say
This check costs two minutes and is a better predictor of total cost of ownership than any specification on the box.
Warranty length is a signal, not a guarantee
Warranty periods vary from six months to lifetime coverage on some components. The length tells you something about the manufacturer's own expectations. But experiences differ enormously even within a brand — some owners report replacement units sent free months out of warranty, others report month-long support arguments ending in a refusal. Warranty is worth having and worth not relying on.
Common questions
How long do robot vacuums last?
Owner reports cluster around three to five years, with a wide spread. Units running nine or ten years exist but almost always involve replaced batteries and brushes. Maintenance and parts availability explain most of the difference.
What is the most important robot vacuum maintenance?
Clearing hair from the main brush and side brushes, ideally monthly. Wrapped hair puts continuous strain on the brush motor, and brush motor failure is one of the most common causes of early death.
Should I replace the battery or buy a new robot vacuum?
If the machine is otherwise working and a battery is available at a reasonable price, replacement is usually far cheaper than a new unit. Check parts availability before your original purchase, because it determines whether this option exists.