Best kettles for hard water: models with top-scoring limescale filters

A tightly fitting fine-mesh limescale filter in your kettle is your number one defence against annoying flakes in your tea or coffee.

That’s exactly what you’ll find in the following selection of the very best kettles for hard water. We also delve into the murky world of limescale: learn more about water hardness and how to keep your kettle clean and limescale-free.

See the top-scoring models from our tests in our guide to the best kettles.

Best kettles for hard water

The following high-scoring kettles from our tests also achieved top marks for the quality of their limescale filters.

You can also buy kettles that have built-in water filters. We’ve tested two: the Russell Hobbs Purity 20760 and Russell Hobbs Purity Brita Filter 22851.

Go to our kettle reviews to see all the models we’ve tested.

Why you can trust our kettle reviews

We buy every single kettle we test – that means no free samples.

Then we subject every kettle to the same independent lab testing and assessments, to identify kettles that are quick to boil, quiet and easy to use. These are our Best Buys.

Our testing completely ignores price, so our kettle reviews are accurate and comparable, regardless of how cheap or expensive the kettle.

Find out more about our testing: How we test kettles.

Where to buy a kettle

• Amazon stocks kettles from Bosch, Breville, Morphy Richards, Russell Hobbs and other brands. Delivery on most kettles is free if you're a Prime member, with 30 days to return if you're unhappy with your purchase.
• Asda sells kettles from Daewoo, Swan, Tower and others, plus its own brand, George. The kettles cost between £13 and £100. Asda offers free click and collect from most of its UK stores, or you can get your kettle delivered from £3.75.
• Currys stocks kettles from Breville, Kenwood, Smeg and Swan. Prices range from less than £10 to £200, depending on the model. If you change your mind, you have 14 days to return it in-store, through a partnered pick-up service or DPD drop-off, depending on the item and payment method. If you're unsure of how to return your item, you can consult Currys’ returns questionnaire.
• DuneIm stocks brands including Churchgate, Russell Hobbs and Spectrum. Prices start from less than £15. It also stocks matching toasters, primarily for its own-brand kettles. Book a delivery from £3.95, or click and collect in-store for free.
• John Lewis offers kettles from brands including Bosch, DeLonghi, KitchenAid and Sage, as well as its own brand. Depending on the model, you might cross the £50 threshold for free delivery; otherwise it's £4.50. If you'd prefer to pick it up yourself, click and collect is free on orders over £30, or £2.50 if you spend less.

What is limescale and what causes it?

Limescale is a hard chalky substance that mainly consists of calcium carbonate, which is found in rocks, seashells and eggshells. It’s usually off-white in colour, but it can also be grey, pink, or even a reddish-brown in some cases.

It's more commonly found in parts of the country with ‘hard water’, which is water that contains large amounts of calcium and magnesium. Over time, if left untreated, it builds up inside your kettle and forms a flaky, scaly coating that won’t disappear on its own.

The problems limescale causes for kettles

There are a few things that can happen if you let limescale build up inside your kettle for a long period of time:

• The heating element in your kettle may become less effective, meaning it takes longer to boil water and your kettle is less energy efficient.
• Your hot drinks start to taste a bit off – particularly tea – as the minerals found in limescale impact how the flavours in tea are broken down.
• You may find loose pieces of limescale floating in your morning cuppa or – even worse – accidentally crunch into one.

That’s why almost any kettle you buy from a reputable manufacturer will come with some sort of limescale filter in the spout. These are designed to separate the limescale from the water as you pour.

To avoid any unwanted flakes in your hot drinks, choose a kettle with a tightly fitting limescale filter made of very thin mesh with no gaps around the sides.

Read about how to remove limescale from your kettle, including using lemon juice and citric acid.

Hard water vs soft water

You might have heard that limescale is a bigger problem if you live in a hard-water area, but what’s the real difference between hard and soft water?

As we’ve mentioned, hard water is water that has a high mineral content, whereas soft water is low in minerals but has a higher sodium content. Hard water is created when rainwater filters through areas with large deposits of limestone or chalk.

Is my water hard or soft?

Whether your water is hard or soft depends on where you live. Hard water is most commonly found in the south east and London, although if you live on the east coast (including large parts of Yorkshire) you might also experience rapid limescale build-up in your kettle.

Most of Scotland, Northern Ireland and Wales have very soft water, as do the south west and north west of England. The Midlands (including Birmingham, Leicester and Nottingham) are a bit of a mixed bag – water in those areas tends to vary from slightly to moderately hard.

Water hardness is measured by calculating how much calcium carbonate (in mg/litre) is present. For an accurate measurement of your own supply, ask your water company.

There are a handful of home tests that will tell you whether your water is hard or soft. You could buy a water testing kit from Amazon or test it yourself using household materials, although this method isn't as accurate.

This is one of the most common DIY methods:

1. Half fill a clean bottle with tap water.
2. Add pure liquid soap (a soap derived from vegetable oils)  one drop at a time and shake for 10 seconds until a lather forms. Don't use detergent, as it creates foam regardless of water hardness.
3. Note how clear the water is. If you have hard water, you'll notice that the water below the suds will be cloudy rather than clear, and the suds themselves will be very shallow and not fluffy.

The more drops of soap needed to make a lather, the harder your water is. This is because soap works by bringing together grime and water to lift away the dirt on your dishes, but in hard water the soap binds to calcium ions and forms an insoluble substance known as calcium stearate – or more commonly, scum.

Further reading: 5 signs you need a water softener

Is it dangerous to consume limescale?

Limescale is a naturally occurring substance and isn't at all dangerous to consume. Tap water containing large amounts of limescale may not taste great though, and it can give hot drinks a slightly salty or bitter aftertaste.

You might have read somewhere that drinking hard water can cause health problems, such as kidney stones, but these claims are completely false. In fact, the minerals found in hard water (calcium and magnesium) are often found in bottled water that you can buy at your local supermarket.

Is it possible to prevent limescale?

While it’s impossible to prevent limescale completely, especially if you live in a hard-water area, there are a few things you can do to reduce the build-up in your kettle.

Use a water filter Using a water filter is the most viable option for most people, as this will remove some of the minerals that cause water to become ‘hard’. There’s no concrete evidence that this will solve your limescale problems completely, but an effective filter will improve your water quality.

Empty your kettle Perhaps the simplest way to keep limescale at bay is to make sure to empty your kettle after every use. Leaving standing water in it for long periods of time can really exacerbate the problem. 

Otherwise, simply clean and descale your kettle every month or so.

You can buy ‘descaler balls’ that claim to collect limescale deposits every time you use your kettle, but these can be pricey and there’s no evidence that they actually work. If you do fancy giving them a go, be sure to check your kettle’s instruction manual first to make sure using one won’t void your appliance’s warranty.

Find out how to descale a shower head and how to clean your toilet.