Limescale can quickly build up inside a kettle, especially if you live in a hard water area, but one cleaning expert has come up with a £2.50 trick that 'really works' to get your kettle sparkling again15:51, 03 Aug 2026If limescale in your kettle has been driving you mad, one cleaning expert claims she's cracked the problem - and her secret weapon costs just £2.50.‌Living in a hard water area means dealing with limescale is an unavoidable part of life. That stubborn, chalky build-up is made primarily of calcium carbonate, which forms when hard water is heated or left to evaporate on a surface. Taps, showerheads and glass shower screens are all common culprits for limescale that's impossible to clean, but one of the worst offenders is something most of us use several times a day - the kettle.‌Every time you boil the kettle for a cup of tea or coffee, minerals in the water separate out and settle at the base of the appliance, gradually forming a crusty layer of limescale. And because most of us don't give our kettles a proper clean after every use, it doesn't take long for that build-up to get out of hand.‌Left unchecked, limescale doesn't just look unsightly - it can actually damage your kettle and cost you money. According to the Express, a heavily scaled heating element has to work harder to bring water to the boil, which pushes up your energy bills over time.How to descale a kettleSo what's the solution? Instagram cleaning enthusiast Lucy has shared what she calls the "most effective" method she's ever tried, and it involves just one ingredient - citric acid - available for roughly £2.50.Content cannot be displayed without consent‌Unlike vinegar, which many people reach for as a home descaler, citric acid is odourless and leaves no lingering taste. It's a naturally occurring acid found in citrus fruits, and it's widely available in powder form from supermarkets and DIY retailers such as B&Q for approximately £2.50.In her video, Lucy showed the inside of her kettle before treatment, where a visible build-up of limescale coated the bottom, with flakes floating loose in the water. To tackle it, she filled the kettle "about a quarter of the way" with tap water, then tipped in "half a box" of citric acid powder, which is roughly 125g.She boiled the kettle as normal, left it to cool, then lifted the lid to reveal the results. The inside was gleaming, with every trace of limescale completely gone.‌"Every time, it amazes me how well it's come out," she said. "Can you see that? Not a single bit of limescale inside. It's honestly like magic. There you have it: the quickest and easiest way to descale your kettle."She added in her caption: "I have tried many ways, and this is by far the most effective! And if you're wondering why you don't have limescale, it's because you get it with hard water!"The clip quickly racked up a flood of comments from grateful viewers who admitted they had been battling kettle limescale for years without finding an effective fix. One commenter wrote: "I needed this!"‌Others were equally enthusiastic about citric acid as the go-to descaling solution. Someone commented: "Citric acid is THE best descaler, nothing else compares! Half a box seems like a lot of citric acid, though; a little goes a long way. We boil full kettles a lot (1.7l), and so we get limescale up the sides too. I fill the kettle to max, pop in the filter near the spout and use 2tbsp of citric acid, and it comes out like new every time!"If you don't have citric acid powder to hand, some commenters pointed out that slicing a lemon and dropping it into the kettle before boiling can also do the trick - since lemons are naturally rich in citric acid. However, for particularly stubborn limescale, using the concentrated powder is likely to give you a more thorough result.Alternative methods to descale a kettleIf you don't have any citric acid to hand but do have lemons or white vinegar, try these two methods instead:‌Vinegar method:Mix solution: Fill the kettle with equal parts water and white vinegar.Boil and soak: Boil the kettle and then leave it for 20 to 30 minutes to soak in.Rinse thoroughly: Empty the solution and rinse inside with fresh water to remove any limescale residue.Boil again: Boil with clean water once or twice to remove any lingering vinegar.Lemon juice method:Article continues belowMix solution: Add three tablespoons of lemon juice, or the juice of two squeezed lemons, to the kettle with a cup or two of water.Boil and soak: Boil the kettle and let it rest for around 30 minutes to soak in and break down the limescale.Rinse thoroughly: Empty the contents and rinse inside with fresh water to remove limescale residue.