Which grass trimmer brand to buy in 2024

According to our latest survey results, the most common faults of grass trimmers vary from one model to the next – whether you own a corded electric, cordless or petrol one.

If your corded grass trimmer develops a fault, it's most likely to be the line feed malfunctioning, with 34% of people saying they had experienced this. For cordless models, 17% also said the line feed malfunctioned, but this was joint with the battery not holding its charge. For petrol trimmers, the most common fault was the engine failing to turn over.

Knowing which brands develop the most faults, and how quickly, is vital when buying a new grass trimmer. Our data is based on a survey conducted in January 2022. We gathered feedback from 3,227 Which? members and the general public to find out how many models remained fault-free in the first seven years of ownership. Brands with insufficient sample sizes were not included (a minimum of 30 respondents is required).

Our survey data takes into account the reported fault rates, the severity of these faults and the speed with which they occurred. In our latest analysis, we've looked at the performance of the biggest grass trimmer manufacturers – including Bosch, Black & Decker, Flymo and Stihl – and have calculated a customer score for each, so you know which brands to choose and which to avoid.

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Best vs worst grass trimmer brands compared

As the table shows, there's a big difference in both our best and worst Which? test scores and the customer scores from our latest survey.

By consulting our expert reviews before you buy, you can be sure that you're investing in a grass trimmer that's easy to use and effective at trimming all manner of grass and weeds quickly and efficiently.

Looking for a new grass trimmer? Take a look at our round-up of best grass trimmers on test.

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The most reliable grass trimmer brands

The table below summarises our latest results. Brands are ranked by their customer score, which relates to whether their customers would recommend that brand. 

In the table below, only logged-in members can view which brands developed the least faults, and which ones members are most satisfied with. If you're not yet a member, join Which? to get instant access.

Petrol vs corded and cordless electric grass trimmers

Common grass-trimmer problems

Corded, cordless and petrol grass trimmers all operate quite differently, so it's not surprising they encounter different problems.

The line feed breaking is a common problem. This is an annoying rather than a devastating issue and can be fixed on the spot. Read our expert guide on how to avoid line-feed problems for more details.

Luckily, most of the top faults are also fixable, or at least won't result in the total breakdown of your trimmer.

Top three common corded grass trimmer faults

1. 34% - Line feed malfunctioned The line feed that's used to cut your grass can break or become jammed. You can usually fix it manually. 
2. 13% - Blades broke Always wipe your grass-trimmer blades with a rag and lubricant after use. It prevents rust and keeps the blades in good condition. Also make use of the plant guard, if it has one, and avoid hitting hard objects that could break or dull the blades. Extra plastic blades are typically supplied with your trimmer. Otherwise, replacements are pretty cheap to buy. 
3. 11% - Electrical failure If you're not confident to look into this yourself, take your trimmer to a garden-machinery specialist or contact the manufacturer to look at having it fixed.

Top three common cordless grass trimmer faults

1. 17% - Line feed malfunctioned The line feed that's used to cut your grass can break or become jammed. You can usually fix it manually.
2. 17% - Battery would not hold charge Lithium-ion batteries eventually lose their ability to hold charge. Store the battery separately from your trimmer and with a minimum of 40% charge remaining.
3. 16% - Battery failed to charge Before you buy a replacement battery, if you have any existing tools from the same manufacturer, check if theirs are compatible. It's useful to have two batteries, so when you're carrying out jobs that will take longer than one battery charge to finish, you have another on standby ready to swap in.   

Ready to cut the cord? Take a look at our cordless grass trimmer and strimmer guide.

Top three common petrol grass trimmer faults

1. 24% - Engine would not turn over If you're not confident to look into this yourself, take your trimmer to a garden-machinery specialist or contact the manufacturer to look at having it fixed.  
2. 12% - Pull cord broke or jammed Another fault that may require specialist attention.
3. 12% - Line feed malfunctioned The line feed that's used to cut your grass can break or become jammed. You can usually fix it manually.

Grass trimmer brands verdicts

Log in or join Which? to get instant access to our grass-trimmer brand verdicts.

Head to our grass-trimmer reviews

Know which grass-trimmer brand you want? Use the links to go straight to our reviews and find your ideal model:

• Stihl grass trimmer reviews.
• Blacker & Decker grass trimmer reviews.
• Bosch grass trimmer reviews.
• Flymo grass trimmer reviews.
• Powerbase grass trimmer reviews.
• Ryobi grass trimmer reviews.

How we calculate the best and worst brands

Which? has a wealth of information on the UK’s favourite garden-tool brands. Every two years, we ask Which? members and the general public to tell us about the garden products they own - from how likely they'd be to recommend a brand, to whether they experienced any faults with it. This year, 8,881 people told us about their products. We calculate a brand's customer score based on the results of our biennial survey.

Our product experience surveys, combined with our extensive lab tests, mean we can recommend the best grass trimmer you should buy.