What they cost to run
The purchase price is the part you plan for. The rest arrives quietly.
Nobody budgets for consumables, and on some models they add up to a meaningful fraction of the purchase price over a few years.
The recurring items
| Item | Typical replacement | Notes |
|---|---|---|
| Dust bags (self-empty dock) | Every 30–60 days | Proprietary. Prices vary hugely between brands |
| Filters | Every 2–4 months | Some washable, some not. Check before buying |
| Main brush | Every 6–12 months | Longer if cleaned monthly |
| Side brushes | Every 3–6 months | Cheap, and they bend rather than wear |
| Mop pads | Every 3–6 months | Only if the model mops |
| Battery | Year 2–4 | The big one. Check it is replaceable at all |
| Electricity | Ongoing | Genuinely small — these are low-wattage devices |
The self-emptying dock trade-off
It converts a weekly chore into a monthly one, which is why most owners rate it the feature they would not give up. It also introduces a permanent bag cost that a basic dock does not have. Some brands are considerably more expensive per bag than others, and bags are almost always proprietary.
Before buying, look up the bag price and multiply by twelve. That is a real annual line item, not a rounding error.
Does it pay for itself?
Price, time saved and running costs, converted into a break-even month.
Open the payback calculator →Washable versus disposable
Filters marketed as washable can usually be rinsed several times before performance drops. Filters that are not washable must be replaced on schedule, and running a clogged one reduces suction more than any specification difference between models.
This detail rarely appears in reviews and materially changes running cost.
Bag and filter prices vary hugely between brands. Look them up before committing to a model. Compare models → Advertising — we may earn a commission.
The check that predicts your total
Before purchase, search the model plus "bags", "filter" and "battery". Note the prices. A machine that is £100 cheaper but uses bags at three times the price is not cheaper after two years.
Parts that are unavailable at any price are worse still — that turns a repairable machine into a disposable one.
Common questions
How much do robot vacuum consumables cost per year?
It varies enormously by brand. The main items are dust bags for self-emptying docks, filters, brushes and mop pads. Look up bag prices and multiply by twelve before buying — some brands cost several times more per bag than others.
Is a self-emptying dock worth the running cost?
Most owners say yes, because it converts a weekly chore into a monthly one. But it introduces a permanent proprietary bag cost that a basic dock does not have, so factor that into the comparison.
Do robot vacuums use much electricity?
No. They are low-wattage devices and electricity is a negligible part of running cost compared with consumables and eventual battery replacement.