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These Christmas tree lights - bought online at AliExpress, eBay and Wish - could catch fire or electrocute you
New Which? research reveals the dangers posed by cheap fire-risk Christmas tree lights sold by third-party sellers through AliExpress, eBay and Wish. Don't buy these lights, or take them down if you already have, as they could light up your Christmas in all the wrong ways.
Nearly half of the Christmas tree lights that we bought from AliExpress, eBay and Wish were electrically unsafe and dangerous to use.
While more than 90% of those we checked - including four models from Amazon Marketplace - failed to meet the standard allowing them to be lawfully sold in the UK.
The most worrying six sets of lights we tested - bought from AliExpress, eBay and Wish - could cause a fire or electrocute you.
The control box on two sets of £4 lights sold on AliExpress and eBay got so hot they melted during our safety tests.
Only one set of lights of the 13 we bought from the four online marketplaces were safe to use, legal for sale, and passed all of our safety tests and compliance checks.
Nine of the lights on test - including four bought from Amazon Marketplace - failed to meet the requirements of the official standard in terms of how robust they are, how they're described, their instructions, their packaging or the markings on them.
Two sets of Christmas lights bought from Argos and John Lewis & Partners flew through all of our safety tests.
Scroll down to watch our video and find out what happens when a Christmas tree catches fire, plus learn what you can do to keep your family and home safe this Christmas.
We also test smoke alarms - our tests reveal not only the quickest to respond, but also the alarms that fail to detect smoke or don't sound loudly enough. See our smoke alarm reviews.
Unsafe Christmas tree lights
Christmas tree lights: fire threat revealed
A genuine fire threat was exposed when we tested two sets of lights bought from sellers based in China. One set of lights was sold through AliExpress, the other through eBay.
Bought through eBay - a charred and molten mess following our short-circuit test
Video: Christmas tree fire
Our video shows what could happen if dangerous lights were to set a Christmas tree on fire. Jeremy James, from Royal Berkshire Fire and Rescue Service, tells us that fire could engulf a tree in less than one minute.
Our vital advice will help keep you and your family safe - find out how to place and maintain smoke alarms
Truly shocking Christmas tree lights
In three separate tests, we uncovered sets of Christmas tree lights that could give you an electric shock.
Burned-out LEDs following our electrical safety tests
In other tests, when we checked the distances between the live and neutral parts of the circuit board, we found that for three sets of lights the distances were up to half of the legal requirement. In the worst cases, this could lead to arcing, where electricity travels through the air, and an electric shock for anybody touching the lights.
Bought from AliExpress - the control box burned and melted during our short-circuit test
What we found when buying Christmas tree lights
Each of the online marketplaces we bought Christmas lights through - so Amazon, AliExpress, eBay and Wish - sold us lights that were either unsafe or didn't meet the compliance standard for lights being sold in the UK.
Our Christmas tree lights test results
How we tested the Christmas tree lights
We run a series of electrical safety tests to find out how safe the Christmas tree lights were. We also checked the pack markings and instructions to see whether they were legal to be sold in the UK.
We test Christmas tree lights at an accredited lab
All of our Christmas tree light tests were carried out by a lab accredited to test to the three relevant standards, EN 60598-2-20, EN 61347 and BS 1363. These cover the testing of strings of lights, the control boxes and the plugs.
Humidity test
We keep all lights in a humid room to see if they continue to work after 48 hours in a damp environment.
Electrical strength test
We check if the lights can withstand the minimum test voltages required without breaking down or becoming unsafe.
Overload
This test is designed to find out if the lights have overload protection. If they don't, they can overheat and could catch fire.
Short circuit
We intentionally short circuit the lights to check that the required fail safes are in place. Products that fail this test could melt or catch fire.
Creepage and clearance
We measure the distances between the live and neutral sections of the circuit board.
Construction test
We record how much force needs to be used to pull the cable out of the control box. We also check to see whether the control box can withstand impacts without falling to pieces, which could prove dangerous.
Legal compliance checks
We measure the size of the plug pins, look to see that instructions are included and check the CE and WEEE symbols are present. We also make sure that the lights are marked appropriately for where they should be used.
Find out how to avoid overloading your plug sockets this Christmas
The safe Christmas lights we bought on the high street
These Argos lights (£8), pictured above, passed all safety tests and compliance checks
Every test was passed by these John Lewis & Partners lights (£15)
They were also packaged correctly, came with instructions for use and were appropriately marked for how they should be used.
How to identify potentially dangerous Christmas tree lights
You won't be able to tell which lights will be safe and which ones could be dangerous just by looking at them. But there are some signs we've seen which could indicate dodgy lights.
Packaging
The six lights pictured above failed our safety tests - they could catch fire or electrocute you
CE and WEEE markings
Christmas lights should carry both the CE mark and the WEEE logo. The CE mark shows the manufacturer or importer claiming that the product complies with the EU legislation applicable to the product.
Look for the CE and WEEE marks on the packaging of any lights you're looking to buy this Christmas
Instructions
Lack of instructions is a bad sign, too. To be lawfully sold in the UK, lights should come with clear instructions.
Price
The worst lights we found in our tests - those where the control boxes melted - cost less than £5 from the online marketplace sellers we bought from.
What you need to know
None of these clues are proof positive that a set of Christmas lights will go on to be dangerous in your home. But if you've bought cheap lights in plain packaging with no instructions, they might well prove to be dangerous.
If you think your lights fit this description, recycle them and buy from a well-known high street store or its online site.
What the online marketplaces told us
We offered each of the online marketplaces the opportunity to comment on our findings about the dangerous or illegal products being sold through their sites.
AliExpress
AliExpress told us that: 'Customer safety is of paramount importance. We have promptly informed the sellers and removed these listings. Merchants need to comply with all regulations in the markets they sell to.
'We have procedures in place to find listings that infringe our policies and we carry out regular monitoring and take action against sellers when our terms of use are violated.'
Amazon
Amazon said: 'All sellers must follow our selling guidelines and those who do not will be subject to action, including potential removal of their account. The products in question are no longer available.'
eBay
An eBay spokesperson told us: 'eBay doesn't permit the listing of unsafe products. The items have been removed and the sellers advised to contact any buyers with the alert and their returns policy.'
Wish
Wish said it was working to have these items removed from its platform.
Which? saysu2026
'Tis the season to be jolly and not the season to be electrocuted or worse. So you should think twice before you buy cheap Christmas lights online - based on our tests, the high street is a better and a safer option.
Natalie Hitchins, Which? head of home products and services, said: 'While they might look like the perfect finishing touch for your Christmas tree, many of the cheap and cheerful Christmas lights we've tested from online marketplaces simply aren't safe, and we've found some even have the potential to set a tree alight.
'The significantly better performance of products bought from high street retailers exposes just how necessary it is to strengthen consumer protections for online marketplaces. The new government must make safety a priority and put the legal responsibility on marketplaces to prevent unsafe products from being sold on their sites.'
Which? is campaigning for online marketplaces to have: greater legal responsibility for products sold on their sites, clearer requirements for taking down unsafe products, better enforcement and greater transparency for shoppers about who they're buying from.
Please sign our petition and demand action against unsafe products