# How much does a robot lawn mower cost to buy and run?

Source: https://mowandedge.co.uk/blog/how-much-does-a-robot-lawn-mower-cost
Published: 2026-10-12
Publisher: Mow and Edge

**In short:** Robot mower prices fall into three broad bands. Entry models with a boundary wire suit small lawns; mid-range models cover larger areas, steeper slopes and better apps; premium models add wire-free navigation and big area ratings. On top of the purchase, budget for installation if you do not do it yourself, regular blade packs, an eventual battery and a small amount of electricity, typically measured in tens of kWh per season.

The ticket price of a robot mower is only part of the story. What you pay depends mainly on lawn size, slope and how the mower finds its way, and then there are the extras: boundary wire and pegs, professional installation, a garage, spare blades and, after some years, a new battery. Running costs are low, and the clearest way to compare them is in kWh rather than money, because tariffs vary. This guide walks through each part so you can budget without surprises.

## Price bands by lawn size and features

Prices change often, so rather than quote figures we group mowers into bands. The main things that push a mower up a band are a larger rated area, a steeper slope rating, wire-free navigation and smarter app features such as zones and maps.

Entry models tend to be compact wired machines rated for a few hundred square metres, such as small Gardena Sileno and Worx Landroid models. Mid-range models cover larger lawns and steeper slopes, for example the Husqvarna Automower 315 is rated for 1,500 m² and a 40% slope. Premium models are mostly wire-free, using RTK satellite positioning, lidar or cameras, and some list very large areas and steep slopes.

| Band | Typical lawn | Navigation | What you get |
| --- | --- | --- | --- |
| Entry | Small, up to a few hundred m² | Boundary wire | Basic schedule, Bluetooth or simple app |
| Mid-range | Medium to large, roughly 500 to 1,500 m² | Boundary wire, some wire-free | Better slope ratings, zones, Wi-Fi app |
| Premium | Large or complex, 1,500 m² and up | RTK, lidar or vision, no wire | Maps, no-go zones, steep slopes, object detection |

Robot mower price bands in words

[See robot mowers under £800](https://mowandedge.co.uk/best/best-robot-mower-under-800)

## Installation and set up

Wired mowers come with boundary wire and pegs for a typical lawn, but complex gardens may need an extra reel and more pegs. You can lay it yourself in an afternoon on a simple lawn; our [boundary wire guide](https://mowandedge.co.uk/blog/how-to-install-robot-mower-boundary-wire) shows the steps. Many dealers offer installation, which can include burying the wire with a cable layer so it is out of the way of scarifiers and aerators.

Wire-free models avoid the wire but may need an RTK reference antenna mounted with a clear view of the sky, and time spent driving the boundary in the app. Camera only models need little hardware but work best on lawns with clear, well defined edges.

## Blades, batteries and other ongoing parts

Most robot mowers use small pivoting razor style blades on a disc. They blunt quickly and are cheap to replace in packs. Makers commonly suggest changing them every few weeks in the growing season, more often on sandy soil or lawns with twigs. Check your manual for the interval and use the maker's blades and screws.

The lithium-ion battery is the main longer term part. Capacity drops with age and use, and after several seasons you may find the mower needs to charge more often. Replacement batteries are a known cost on any cordless tool, so check that spares are sold for your model before you buy. Other parts that sometimes need replacing include wheels, the blade disc and, on wired systems, wire connectors after a break.

- Blade packs: several changes per season
- Battery: once every few years, depending on use and storage
- Wire repair connectors and spare wire for wired mowers
- Optional garage or shelter for the dock
- Winter service at a dealer, if you prefer

Note: Before changing blades, press the stop button, switch the mower off or disable it with the PIN, and wear gloves. Never lift a running robot. Replace a swollen or damaged battery only with the maker's part, and follow the manual.

## Electricity: how to estimate kWh per season

Robot mowers use little power compared with household appliances. You can estimate it yourself from the battery label. Multiply volts by amp hours to get watt hours, multiply by the number of charges, then add a margin for charger losses and the dock's standby use.

Here is a worked illustration, not a measured figure. An 18 V battery of 2 Ah holds 36 Wh. If it fully recharges three times a day, seven days a week, for a 30 week season, that is 36 x 3 x 7 x 30 = 22,680 Wh, or about 23 kWh. Add around 20% for losses and standby and you get roughly 27 kWh for the season. A bigger mower on a larger lawn will use more, a small one on a small lawn less. Multiply your figure by your unit rate on your bill to see the cost.

1. Read the battery voltage (V) and capacity (Ah) from the label or manual.
2. Multiply V by Ah to get Wh per full charge.
3. Estimate charges per week from the app's run history or your schedule.
4. Multiply by the number of mowing weeks in your season.
5. Add about 20% for charging losses and standby, then divide by 1,000 for kWh.

## How to keep total cost down

Buy for your real lawn, not the biggest rating you can find. Measure with the [lawn-area calculator](https://mowandedge.co.uk/tools/lawn-area-calculator), allow some headroom for slopes and narrow passages, and stop there. Paying for wire-free navigation makes most sense where wire would be awkward, such as large or complex gardens; on a small rectangle a wired entry model does the same job.

Look after the battery: store the mower clean, charged and indoors over winter as the manual describes. Change blades on time, since blunt blades tear grass and make the mower work harder. Our [best robot lawn mower guide](https://mowandedge.co.uk/best/best-robot-lawn-mower) compares models across the bands.

## Frequently asked questions

**How much is a robot lawn mower compared with a cordless mower?** Even entry robot mowers usually cost more than a good cordless push mower. You are paying for automation and time saved rather than cutting power.

**Do I need to pay for installation?** Not always. Simple lawns are well within a confident DIY job. Large, sloping or complex gardens, or a wish to bury the wire neatly, are good reasons to use a dealer.

**Are wire-free robot mowers worth the extra?** On large or complicated lawns, or where wire would be cut by regular lawn work, they can be. On small simple lawns a wired model is usually the better value.

**How much electricity does a robot mower use?** Work it out from the battery: volts times amp hours, times charges per season, plus about 20%. For many home models that lands in the tens of kWh a season.

## Buying guides on this topic

- https://mowandedge.co.uk/best/best-robot-mower-under-800
- https://mowandedge.co.uk/best/best-robot-lawn-mower
- https://mowandedge.co.uk/best/best-wire-free-robot-mower

## Sources

- [Energy Saving Trust](https://energysavingtrust.org.uk/)