5 safe ways to unjam a paper shredder

From letting the motor cool down to using shredder lubricant, our tips will help you get your jammed shredder back up and running.

In a survey of more than a thousand Which? members in July 2023, 43% of owners told us their shredder had become blocked. Members also have some pretty varied ways to solve the problem – find out which we recommend below. 

Read our best shredders reviews to find out which came out on top in our rigorous testing.

1. Let it cool down

If you're shredding lots of paper and not giving your machine enough rest between batches, then the motor can overheat and stop working.

Overheating doesn't happen as often as blockages. Just 18% of our survey respondents reported it as an issue they've experienced, but it's common enough to be aware of.

Try unplugging the shredder and letting it cool down before attempting to clear the blockage again. Some machines have a light to indicate that the overheat function has kicked in and you can't start shredding again until it's turned off. 

Check the instructions provided with your shredder to see how long you should leave it for. Many shredders can only run for a few minutes before needing a cool-down period of around 30-40 minutes.

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2. Cycle between reverse and go functions

Most shredders have the option to reverse, which is designed to help avoid blockages. Our tests found that the best shredders at clearing blockages have a reverse function that works automatically once a jam has been detected.

If you need to clear the blockage manually, 30% of people we surveyed found success when constantly alternating between the reverse and forward functions. 

Don't do this for too long, or too quickly, as it can be quite demanding on the machine and may run the risk of it overheating.

Often, you're left with a clump of paper which you'll need to carefully remove in order to effectively clear the machine. Sometimes, this will take quite a bit of force if the shredder simply won't let go.

3. Empty the bin

A full bin could be the cause of the blockage, as there isn't anywhere for the paper to go once it's shredded.

It may seem simple, but even if it doesn't look completely full, try switching off your shredder and emptying the bin. This method resolved the jam for 13% of people we surveyed. 

Make sure you're recycling whatever you shred, as it will be used for products such as toilet paper, coffee filters or towels, to name a few.

To avoid having to empty your shredder so often, you could opt for a larger machine. Most tend to be between 13 and 16 litres, although we've tested one as large as 26 litres. 

And remember, emptying a shredder bin can be messy, especially when it shreds into tiny pieces, so keep one of our best vacuum cleaners close by. 

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4. Use card to push through a jam

If the solutions above haven't worked, it may be worth trying to use a piece of card to remove the blockage. Avoid using tools such as tweezers or needle-nose pliers, as these could end up harming the motor, the blades or your fingers.

For this to work, you'll need a stiff and tough bit of card, similar to that of a cereal box. Take care not to use card that's too thick, or you could make the problem worse. 

While the shredder is on and running, carefully push the card between the teeth with some pressure to help squeeze out the blockage. You could also try folding the card into a point, so it's easier to position near the area that's blocked.

Once the stubborn pieces are removed, feeding through more paper can then help to clear the rest of the jam.

5. Use a shredder lubricant to prevent paper jams

Lubricating your shredder should help to prevent jams and make it easier for paper to pass through smoothly. 

Leading manufacturers such as Fellowes advise that you lubricate your shredder every time you empty the bin, or at least twice a month. Despite that, 69% of our survey respondents told us they don't do this at all.

They should, as it seems to make a real difference. Nearly half of those who lubricate their shredder told us they think it made their device more resistant to jams. 

When selecting a lubricant, make sure you use vegetable-based oils instead of aerosol oils, as the latter are petroleum-based and can pose a fire risk. 

The cheapest price we've found for a 335ml bottle of Fellowes shredder oil is £9.50, while 473ml of Rexel shredder oil is £20.

If you don't want to use a bottle in case of spillage, you can get lubricant sheets instead. You feed these into the machine like a normal sheet of paper. The cheapest we've found are a pack of 12 on Amazon for around £12. 

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Things we've learned testing shredders

• Don't use your bare hands to try to unpick the jam - especially when it's plugged in. Even though most shredders don't have a throat big enough for fingers, it's a potential safety risk to get your hands near the blades.
• Avoid loading the shredder beyond the maximum pages per feed we calculated in our testing. This tends to be slightly more than the manufacturer recommends. Try any more than this, however, and the shredder is at serious risk of jamming up.
• Some shredders have a much more effective reverse function, so read our shredder reviews and opt for one of these if you're on the hunt for a new machine that's less likely to get blocked. 

Shredder types explained

Strip-cut shredders

The traditional type of shredder - also known as ribbon-cut - slices paper up into long strips. While you can still get shredders like this, they're less common due to the potential for the strips to be put back together, which is a security risk.

Where to buy the strip-cut shredder we've tested

Cross-cut shredders

These are a much more secure type of shredder than strip-cut machines, as it would be much harder to reassemble a shredded document. Sometimes also known as diamond-cut shredders, they cut paper up into small pieces that are shaped like wedding confetti. 

Cross-cut shredders we've tested and where to buy them

Micro-cut shredders

These shredders come with the highest security rating, as they slice documents into tiny pieces that would be almost impossible to put back together. If security is your primary concern, these are the ones to go for.

Micro-cut shredders we've tested and where to buy them

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