Comparison · Updated May 2026
Cordless vs Petrol Lawn Mowers
The biggest decision in mower buying isn't brand or model: it's power type. Here's an honest side-by-side based on manufacturer specs, running-cost data and verified owner reviews of both.
Head-to-head comparison
| Factor | Cordless | Petrol |
|---|---|---|
| Best lawn size | Up to 800 m² | 500 m² and up |
| Upfront cost | £150-£700 | £200-£900 |
| Cost per mow | 1-3p | 30-80p |
| Noise | 78-84 dB | 92-100 dB |
| Weight (typical) | 9-18 kg | 22-35 kg |
| Starting | Push button | Pull cord / key start |
| Runtime | 20-60 mins per battery | Unlimited (refuel) |
| Maintenance | Blade, clean deck | Oil, plug, fuel, blade, service |
| Long-term cost | Battery replacement 5-8 yrs | Annual service + fuel |
| Emissions | Zero at point of use | CO2 + hydrocarbons |
| Sunday mowing | Quiet enough for 8 AM | Neighbours will hate you |
When cordless wins
For the typical UK garden under 600 m², cordless is the better choice. It's lighter, quieter, cheaper to run, starts instantly, and the battery shared across your other garden tools makes the investment smarter. Most UK households fall into this bracket.
Top picks: Gtech CLM 2.0 for small gardens, EGO LM2122E-SP for large. See our full cordless mower guide.
When petrol wins
Lawns over 800 m², heavy wet grass, steep slopes, or if you genuinely prefer the feel and sound of a petrol engine. Petrol mowers also last longer in terms of absolute lifespan - a Honda engine will run for 15-20 years with basic servicing. Cordless batteries max out at 8-10 years.
Top picks: Mountfield SP46 for value, Honda HRX 476 for premium. See our full petrol mower guide.
The honest verdict
If you're buying your first mower in 2026, go cordless unless you have a specific reason not to. The technology has caught up. The running costs are lower. The noise difference alone - being able to mow at 8 AM on a Sunday without incident - is worth the switch for most people.
If you're replacing a petrol mower and your lawn is under 600 m², switch to cordless. If it's over 800 m², stick with petrol or consider a robot mower. In between? Test both if you can - B&Q and Screwfix both have generous return policies.