How to descale a kettle: Our top tips for removing limescale

It’s a job many of us put on the long finger, but descaling your kettle regularly will make it boil more quickly, use less electricity and generally extend its lifespan. Even the best kettles can be prone to limescale build-ups, particularly if you live in a hard water area; these chalky deposits can look unsightly and also negatively affect your kettles’ performance.

To learn a little bit more about what limescale is and how it forms in your kettle, check out the guide section below. However, if you’re ready and eager to get cleaning, you can jump straight to our step-by-step descaling instructions. At the bottom of the page, we’ve also included some tips and tricks for preventing limescale build-up and keeping your kettle running smoothly.

What is limescale and how does it affect your kettle?

Around 60% of the UK is made up of hard water areas, meaning that there’s a high level of mineral content in the water. While hard water isn’t hazardous to your health, it can play havoc with your appliances, increasing the rate at which limescale builds up in things like your dishwasher, coffee machine or boiler.

A hard, chalky off-white deposit, limescale is mainly made up of calcium carbonate. Limescale build-ups occur in areas with hard water, which forms when rainwater passes through limestone, chalk and other mineral deposits. As it passes through, the water takes on a high level of minerals like calcium and magnesium.

When you boil hard water from your tap in the kettle, these dissolved minerals solidify and stick to the interior of your kettle to form limescale. As well as via boiling, limescale can also form over time when water is left standing in your kettle.

Limescale affects the efficiency of your kettle because it is a natural insulator. Build-ups of limescale slow the transfer of heat from your kettle’s heating element to the surrounding water, making it take longer to boil and increasing its operating volume.

Already one of the more energy-hungry appliances in your home, the longer boil times of limescale-ridden kettles mean they will add a bit more onto your energy bills at the end of the month.

The continuous increased strain your kettle goes through to reach a boil can also reduce its lifespan and force you to replace it sooner than you would otherwise need to. Limescale can even negatively impact the flavour of water produced by your kettle, ruining perfectly good cups of tea and coffee.

READ NEXT: Best bean-to-cup coffee machine

How to descale your kettle

If you want to descale your kettle right away, you can do so using a few simple household items, which I’ll cover below. However, the most straightforward way to deal with limescale build-up in your kettle is to use a specific descaling product. There are plenty of options out there, but one of the most well-known brands is Oust, which is what I use at home myself. To descale your kettle using this product, follow these steps:

1. Half fill your kettle with water and set it to boil
2. Remove your kettle from its base and place it in an empty sink
3. Slowly empty a sachet of descaler into your kettle and leave it to sit for ten minutes. For heavy scale, you can use two sachets of descaler
4. Empty your kettle and then rinse with cold water. Fill your kettle with clean water, boil and rinse again

Now, let’s look at some methods that use household items. To tackle a basic build-up like calcium carbonate, you can try using household acids like lemon juice or white vinegar:

1. Fill your kettle with either equal parts water and white vinegar, or water and thin slices of lemon. You can also use bottled lemon juice if you don’t have any actual lemons to hand – a couple of teaspoons should do the job. Make sure to fill your kettle up to the height of the limescale, though be sure to not exceed the maximum fill line or go below the minimum line
2. Boil the kettle, allow it to cool, then boil again
3. Pour out the contents and rinse thoroughly to remove any lingerie aftertaste of lemon or vinegar
4. If this method doesn’t shift the limescale, you can try increasing your acid to water ratio or switch to a different method. For increased cleaning power, you can source specialised cleaning vinegar, which is stronger than its kitchen equivalent

Our next suggestion is to tag in the heavyweight champion of home cleaning solutions: bicarbonate of soda.

1. For this more direct cleaning method, you can begin by mixing tablespoons of water and a bicarbonate of soda in a 1:3 ratio to create a mildly abrasive cleaning paste
2. Make sure your kettle is cool and switched off at the wall, then apply your cleaning paste to the affected areas and allow it to dry
3. Next, use a brush to scrub away the paste and the limescale underneath. For delicate areas like in and around the heating element, we suggest using a toothbrush
4. If you don’t fancy scrubbing, you can also use the boiling method with bicarb. Add a tablespoon of bicarbonate of soda to 500ml of water and boil several times, allowing the kettle to cool between boils. Afterwards, rinse thoroughly with cold water

READ NEXT: Best kettle and toaster set

How to prevent limescale build-up in your kettle

There are a number of different things you can do to prevent or slow the build-up of limescale inside your kettle. From everyday tips to preventative products, following any of the advice below will help stop descaling your kettle becoming an everyday task in your home:

• To reduce limescale build-up from standing water, empty your kettle fully after each use. Giving the inside of the kettle a quick wipe down inside to dry it more thoroughly will also help

• Don’t overfill your kettle. Not only is this a bad idea because it uses more energy, it can also cause limescale to build up more quickly, due to the larger amount of dissolved minerals present in larger volumes of water

• Use a water filter jug. If you live in a hard water area, filling your kettle with filtered water can ensure there is no mineral content in your water to lead to limescale build-up

• Similarly to using a filter, keeping some bottled or distilled water on hand for using in your kettle will also head off limescale formation

• If your limescale issues are serious and widespread, you may want to invest in a water softening system. These systems can be attached to your water supply, where they can chemically soften your water before it gets to your appliances, preventing limescale build-ups in your pipes, dishwasher, washing machine, kettle and more