Why Does My Trimmer Line Keep Breaking?

A weed trimmer is an invaluable tool for making your lawn look flawless. They work by simply spinning a strong plastic line fast enough so that it can easily chop through grass.

However, it is not so easy when the line keeps breaking on you.

The main reasons why your trimmer line keeps breaking are:

  • Low quality line
  • Line is not designed for your trimmer
  • Not rolled properly
  • Too much, or not enough line used at once
  • Line is worn out

Keep reading to learn the easy remedies for these common weed trimmer problems as well as why they happen to begin with. 

Low Quality Line

The easiest problem to fix is a low-quality line. Look, for some things, you have to just buy the good stuff.

If you bought a cheap line from the big box store, it is cheaply made with inferior materials.

That means it is going to break way faster than it should. Here are some qualities you should look for in a good roll of trimmer line:

  • Round cut is the strongest, then star. Square is the weakest.
  • Try to buy line that comes pre-rolled on an attachable reel. That way you do not have to roll it yourself and risk damage.
  • Look for a thicker line. The thinner it is, the easier it is going to break.
  • If none of the pre-rolled lines fit your trimmer, go for a bigger reel. The more you have, the better.

The Line Is Not Designed for Your Weed Trimmer

Of course, if buying a higher quality trimmer line did not work, it could also be possible that you are using one that is not designed for your trimmer in the first place.

If the line is too thick, it will break at slower speeds and without feeding more line through. If it is too thin, will feed through and cut off way too easily. 

Either way, that line is going to keep breaking and you are going to keep running out.

Consult your instruction manual for exact line specifications for your trimmer after you use up the factory installed line.

Your Line is Not Rolled Properly

Another possibility is that you did not roll the line properly. As trimmer line weakens at the ends, it is meant to naturally fall off.

With the extra space now under the grass guard, more line will automatically feed out of the reel. Ideally, you actually should never have to “tap” out more line.

However, in practice, occasionally having to tap out more line is perfectly normal. But of course, if you have to do it every few minutes because the line keeps breaking, that understandably becomes annoying.

It is most likely because the line is bound around the reel incorrectly, meaning it cannot automatically slip out. Follow these steps to properly roll up your trimmer line:

  1. Detach the spool from the weed trimmer head. Usually these can be popped off with a push and twist. If you are not sure, consult your owner’s manual for removal instructions.
  2. Pull off roughly 20 feet of line from your reel
  3. Grab one end and find the hole in the middle of the spool.
  4. Stick the end into the hole.
  5. Pull on the line until you reach the middle of it. Now you should have two equal lengths, like shoelaces.
  6. Take both ends and start winding the around the spool at the same time.
  7. The most important thing to remember when winding the line: try to avoid crossing as much as possible. Keep wrapping straight on, and only cross slightly over when you need to start a new row. The more you cross, the more risk of the line becoming caught and causing feeding issues.
  8. When you have about 8 inches of line left on both sides, feed both ends through the holes on the side of the trimmer head.
  9. Latch the spool in place and you should be good to cut those weeds!

You can check out this video from Mr. Hardware to see how it’s done: 

Too Much or Not Enough Line is Being Used at Once

If none of that works, the problem might just be with your trimming habits. Do not worry, this is easy to fix.

Either of two things are happening here: either you are letting the line become way too long, or you just are not using enough.

If your line is too long, say about a foot, it is essentially going to start slapping walls and becoming caught on fences, rather than just powering through the grass cut and moving on.

Any excess wear and tear on your line is going to break it at a much faster rate.

On the contrary, if your line is only a couple inches short, the grass tends to win the battle, not the line.

That is because without enough line and the resulting torque, it does not have enough strength to cut. Instead, the string wears out and needs to be replaced faster.

In general, it is best to keep about 8 inches of trimmer line showing for the perfect combination of an easy cut and low line usage.

The Line May be Worn Out

For most weed trimmers, whether it breaks often or not, more line can be tapped back into place. However, this is not the case with certain weed trimmers.

Some require a much stronger type of line that is precut and simply placed into the head. (No wrapping necessary.) 

If you have this kind of trimmer and the line is breaking too often, keep the following in mind:

  • It is absolutely essential you buy the highest quality line, as replacement is a bigger hassle.
  • Be careful to avoid hitting objects like sidewalks and walls, as this will make the line wear out faster.
  • Make sure you are not cutting the line too long. Even in these kinds of trimmers, if the line is too long, it just takes more damage.
  • Too much power. You should not constantly run this type of trimmer at the highest possible setting. Doing so may cut a little faster, but it also makes the line take a lot more abuse.

The Best Weed Trimmer Brands

If all else fails, it might just be that your trimmer is not producing enough power anymore, which hurts the effectiveness of the line. You may want to check out one of these other brands of weed trimmers instead.

Black & Decker

This 14-Inch electric weed trimmer from Black & Decker is exactly what you need (buy on Amazon). This company is known for its quality products and this is no exception.

It plugs in so you do not have to deal with gasoline or constant dead batteries. In addition, there are package options with additional spools, so you do not even need to worry about finding the right brand later.


The Makita XRU15PT1 trimmer kit, on the other hand, ensures you will never need more weapons against weeds again.

It comes with four batteries and an all-out charging station so you will never have a battery die on you again. No more dragging the extension around the yard and accidentally cutting it.

You can also buy it on Amazon.

The Final Breakdown

The most important thing you need to remember about weed trimmers, and lawn equipment in general, is that it is all about quality.

Buy the good trimmer line and you will not have to keep buying the cheap stuff, which will cost you more money in the long run. 

Similarly, if you buy a really high-quality trimmer like the Black & Decker or Makita, they will work smoother. The smoother the operation, the better luck you will have with keeping your line intact. 

Peter Toth

Hi! I'm Peter, the owner of BackyardGadget. Working around the house has always been a big part of my life. I've created this site to share my experience, and to help people choose the right tools for the job. Thank you for stopping by!

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