Robot lawn mowers remove most of the work involved in cutting the grass, but they aren’t maintenance-free. The good news is that routine jobs are generally small: keeping the mower clean, checking the blades and wheels, and preparing it properly for winter.
What matters before buying is understanding which parts are consumables, how often you’ll need to intervene and whether servicing can be handled at home or requires a dealer.
The quick answer
Robot mower maintenance is usually light but regular. Expect to remove grass from underneath the mower, inspect or replace cutting blades, keep wheels and sensors clean, and store or prepare the machine correctly for winter. The battery is a longer-term replacement item rather than something you should normally change every season.
In this guide
What maintenance does a robot mower actually need?
For most owners, maintenance falls into four areas: blades, cleaning, battery care and seasonal storage.
You don’t need to service the mower every time it cuts. A better habit is to inspect it periodically and deal with anything that is beginning to accumulate or wear.
During the mowing season, check:
- Whether grass is building up underneath
- Whether the blades are damaged, blunt or no longer moving freely
- Whether mud or grass is affecting wheel traction
- Whether cameras and other exposed sensors are clean
- Whether the charging contacts are clean and undamaged
A mower working on dry, obstacle-free grass may need less attention than one operating on wet clay soil beneath trees.
How often do robot mower blades need replacing?
There isn’t one replacement interval that applies to every robot mower.
Some use small pivoting razor-style blades, while others use different fixed or heavy-duty cutting systems. Lawn size, mowing hours and garden debris also affect wear.
Instead of replacing blades simply because a particular number of weeks has passed, inspect them for wear and follow the manufacturer’s interval for your model.
What wears blades out faster?
- Small stones
- Twigs and fallen branches
- Exposed tree roots
- Hard objects hidden in long grass
- Very large mowing workloads
If the grass begins looking torn rather than cleanly cut, the blades are one of the first things worth checking.
When replacing blades, replace the screws or other mounting hardware when the manufacturer specifies it. Correct blade installation matters because the cutting system rotates at speed.
How often should you clean a robot mower?
Cleaning should be based on conditions rather than a rigid weekly schedule.
Dry grass clippings may create relatively little buildup. Wet mowing can produce a thick layer of compacted grass underneath the mower much more quickly.
Pay particular attention to:
- The cutting disc and blade area
- Front and rear wheels
- Charging contacts
- Cameras and navigation sensors
Grass wrapped around a wheel or packed into the cutting area is more important than making the mower cosmetically spotless.
Can you wash it with a hose?
Check the instructions for your exact mower.
Water-resistance ratings and approved cleaning methods differ between models. Some manufacturers permit washing particular machines with a hose, while others specify brushing or wiping instead.
Don’t assume that being able to operate in rain automatically makes a mower suitable for pressure washing.
Still choosing a robot mower?
Compare lawn capacity, slopes, navigation systems, prices and ratings before deciding which model suits your garden.
How long does a robot mower battery last?
The lithium-ion battery is a consumable component, but it should be considered a longer-term maintenance item rather than routine seasonal maintenance.
Battery lifespan varies according to the mower, charging cycles, operating conditions, storage and how heavily it is used.
As the battery ages, you may notice the mower spending less time cutting between charges or returning to its charging station more frequently.
Before buying an expensive robot mower, check something that is easily overlooked: can the battery be replaced, and how is replacement handled?
On some machines it may be straightforward; others may require an authorised dealer or service centre.
What about software updates?
Modern wire-free mowers increasingly rely on software for navigation, obstacle detection, mapping and app features.
Firmware updates can therefore be part of ownership, particularly on RTK, LiDAR and vision-based machines.
Many connected models can receive updates through Wi-Fi, mobile data or their companion app, but the process varies by manufacturer.
Keeping firmware current can be more important on a robot mower than it is on a conventional lawn mower because software directly influences how the machine navigates your garden.
What should you do with a robot mower in winter?
Once grass growth slows sufficiently, repeatedly sending the mower onto cold, wet or frozen grass achieves very little.
Manufacturer winter procedures vary, but commonly include:
- Cleaning the mower thoroughly
- Inspecting the blades and cutting system
- Charging the battery as instructed
- Storing the mower somewhere dry and protected from frost
- Following the manufacturer’s instructions for the charging station and power supply
Don’t assume every component should automatically be left outdoors or automatically brought indoors. Charging stations, power supplies, batteries and RTK equipment can have different storage instructions.
Use the manual for your particular installation before disconnecting equipment for winter.
Should you have a robot mower professionally serviced?
It isn’t necessarily required every year for every mower.
Basic jobs such as cleaning and blade replacement can often be handled by the owner where the manufacturer permits it.
Dealer servicing becomes more relevant if the mower develops faults, needs parts you cannot replace yourself, requires specialist diagnostics or the manufacturer specifies servicing as part of its maintenance programme.
Before purchasing, particularly at the premium end of the market, check whether there is convenient UK service and parts support. A sophisticated mower is much less convenient if a minor fault leaves it unusable for weeks.
How much should you budget for maintenance?
Avoid relying on one supposed “annual maintenance cost”. Two owners of the same mower can have very different costs depending on lawn size, blade wear and whether professional servicing is used.
A better way to compare models is to price the individual consumables:
- A set of replacement blades and fixings
- Any manufacturer-recommended service parts
- Professional servicing if required
- Longer-term replacement battery cost
Also check availability. Cheap consumables are little help if the correct parts are difficult to obtain.
Is robot mower maintenance a lot of work?
Usually, no. The routine workload is small compared with regularly mowing the lawn yourself, but a robot mower isn’t a machine you can completely ignore.
Keeping the underside, wheels and sensors clean and replacing worn blades will deal with much of the routine maintenance. Battery replacement and repairs are less frequent but potentially more expensive.
When comparing mowers, look beyond the purchase price and check how easy it is to buy blades, replace the battery and obtain UK servicing. Those details become much more important after you’ve owned the mower for several years.
Find the right robot mower for your garden
Use your lawn size, slopes and priorities to narrow down suitable models, or compare robot mowers side by side.