How to descale your kettle - and the best natural product to use
- Lucinda Smalley
- Nov 27
- 10 min read
Updated: 6 days ago
If you live in a hard water area (hello from Poole 👋), your kettle probably scales up faster than you can drink your morning cuppa. Those white flakes in your tea, the louder-than-usual boil - that’s all limescale doing its thing.
The good news? Getting rid of it doesn’t have to be a faff. You don’t need harsh chemicals or a kitchen that smells like a chip shop. There’s one natural product that works quickly, safely and better than anything else I’ve tried:
Citric acid
It's my go-to for removing limescale, and the easiest way to get your kettle looking like new. Here’s why.
In this article:
Why kettles scale up so quickly
Limescale builds up more quickly on kettles than almost any other appliance because a perfect storm is happening inside. Heat encourages the minerals in the water to harden and stick onto surfaces. With water being boiled multiple times a day — each cycle leaves behind new mineral deposits — and steam condenses around the lid, spout and sides, it adds another layer each time.
The harder your water is, the more quickly your kettle will scale up — in very hard water areas this can be within days, not weeks.
If you’re not sure how hard your water is, you can either check your supplier’s website or use a simple test strip at home. I’ve got a full guide on how to test water hardness here.
Why citric acid is the best natural kettle descaler
Citric acid really is the unsung hero when it comes to tackling limescale. I was delighted to speak to the Telegraph & Argus recently about how great it is and to urge more people to use it.
It’s a naturally occurring compound found in citrus fruits (think lemons and limes). And when it comes to limescale, it’s super effective.
Here’s five reasons why I love it:
1 ~ It dissolves limescale fast
Think minutes, not hours — because it actually breaks the scale down.
2 ~ It’s food-safe and natural
No harsh chemicals. No fumes. No lingering smell (like other methods - more on those soon).
3 ~ It won’t damage your kettle
Safe for stainless steel and glass.
4 ~ It’s cheap and easy to find
You’ll find it on Amazon, at B&Q and even in some supermarkets - and a single box or bag lasts ages.
5 ~ You can use it on limescale everywhere
Kettles, taps, toilets, showers, dishwashers, washing machines - the lot.
Honestly? I’ve tried vinegar, lemon juice, bicarbonate of soda, and shop-bought descalers… and citric acid wins every time.
How to descale your kettle with citric acid
This is the method I use at home:
1. Fill your kettle halfway with water.
2. Add 1–2 tablespoons of citric acid. Use one tablespoon for light scale and two for heavier build-up. As soon as you drop the citric acid in, you’ll hear it fizzing away - that’s it working its magic.
3. Boil the kettle. It may sound a little louder than usual, but don’t worry - that’s normal.
4. Leave it to sit for 15–20 minutes.
5. Clean the mesh spout filter (if you have one). If your kettle has a little mesh filter that clips in behind the spout, pop it out before you start. Once the kettle has boiled and the citric acid solution is cooling, drop the filter straight into the warm mixture to soak. It will dissolve the chalky build-up without any scrubbing.
6. Pour it out and rinse.
7. Boil fresh water once and discard before making your next drink.
Extra steps if needed
For limescale around the spout or lid. Soak a couple of pieces of kitchen paper in a strong citric acid solution (150ml warm water with 1 tbsp citric acid). Once the kettle is cool, lay the paper over the area for 10 minutes, then remove it and wipe down with a wet microfibre cloth.
If stubborn bits remain after following steps 1 - 7, repeat the process.
That’s it. No scrubbing. No harsh smells. No effort.
Check out my results
I used this this exact method on a heavily scaled kettle. I added in the extra kitchen paper step for the spout and lid. These are realistic results using citric acid, no editing, no secret scrubbing. As you'll see it's not completely perfect, but the transformation is huge!
The science bit: how citric acid dissolves limescale
If you enjoy knowing why things work (same 🙋♀️), here’s the chemistry bit behind it. Hard water is full of minerals like calcium and magnesium, and when you heat that water in a kettle, boiler or shower, the minerals stick to surfaces forming calcium carbonate (limescale to you and me).
When citric acid and calcium carbonate meet, a chemical reaction happens that turns everything into calcium citrate, carbon dioxide and water. Basically, the acid breaks the limescale apart and transforms it into something that dissolves easily in water. That satisfying fizzing you hear when you drop the citric acid into the kettle? That’s the carbon dioxide being released as the reaction happens. That’s why citric acid works so effectively — because it’s actually breaking down the minerals.
Because the resulting calcium citrate rinses away cleanly, the whole process is non-toxic, gentle on surfaces, safe for food-use appliances and far kinder to the environment than harsher chemical cleaners.
Bonus: you can use citric acid to descale everything
This is genuinely one of the reasons I love it. Citric acid works brilliantly in washing machines (run an empty hot cycle with a couple of tablespoons), on shower heads (soak in warm solution for half an hour), on shower screens and glass (spray and wipe to lift cloudy mineral build-up), and on taps and fixtures (wrap kitchen paper soaked in solution around the base).
It’s also excellent in toilets and can be used in many coffee machines as long as you check the manufacturer’s instructions. Once you start using it, you’ll reach for it constantly.
Other ways to reduce limescale in your kettle
Descaling gets rid of the limescale, but how do you reduce it in the first place?
Get a water filter
Filtering your water before you put it in your kettle makes a noticeable difference, whether that’s with a jug, a tap-mounted filter, an under-sink system, or a 3-in-1 filtered tap. In the homes we visit through Plumberly, filtered water genuinely reduces the speed at which kettles scale up.
Read more about the different types of water filter here.
Hard water kettles
Choosing a kettle designed for hard water also helps. Look for models with stainless steel interiors, wide openings that make cleaning easier, and removable mesh filters that you can rinse weekly.
Descaler ball
A stainless steel descaler ball can also help by attracting some of the minerals before they stick.
Small habits
Emptying your kettle after each use is another tiny change that has a big impact, because limescale forms fastest when water sits and cools. And finally, try not to boil the same water repeatedly, reboiling encourages even more minerals to harden and cling to the kettle.
How often you should descale your kettle
If you’re in a hard water area — anywhere across the south of England, most of London, and large parts of the Midlands — you’ll get the best results by descaling every one to two weeks. In moderate areas, once a month is normally enough.
You’ll know it’s time when your kettle starts boiling louder than usual, looks cloudy inside, leaves flakes in your drink, or simply feels slower than it used to. A regular citric acid clean genuinely improves the taste of your drinks and helps your kettle last longer.
Common mistakes when descaling a kettle
There are a few easy mistakes people make when trying to descale. Using too little citric acid is one of them — a tiny teaspoon won’t touch heavy scale. Another is not giving the reaction long enough to work; the magic usually happens in those fifteen to twenty minutes of soaking.
Scrubbing heating elements is also a no-go because it can damage protective coatings. And then there’s the classic “vinegar and bicarb volcano” — fun for kids, useless for descaling. Finally, forgetting to boil fresh water once after cleaning can leave a tiny citrus tang, so it’s always worth that final rinse boil.
Other natural methods and why I don’t rate them
Other popular alternatives like vinegar, lemon juice and bicarbonate of soda can help, but they’re not as effective. Vinegar works a lot like citric acid, but it’s weaker so it takes longer and might not be tough enough for heavy limescale — plus you need to put up with the smell.
Lemon juice is even weaker than vinegar. Bicarbonate of soda is better for tackling odours and surface grime; it doesn’t actually dissolve limescale, so you’re mainly scrubbing it off rather than breaking it down.
Citric acid, on the other hand, is faster, cleaner, odourless, safer for most surfaces, more environmentally friendly and less likely to damage seals or coatings. Once you switch, you won’t go back.
Comparison: citric acid vs other methods
Here’s a simple side-by-side look at the most common descaling options:
Method | Effectiveness | Smell | Speed | Cost per use | Best for |
Citric acid | ⭐⭐⭐⭐⭐ | None | Fast | Low | Light - heavy scale |
Vinegar | ⭐⭐ | Strong | Slow | Low | Light scale |
Lemon juice | ⭐ | Mild | Slow | Medium | Light scale |
Shop descaler | ⭐⭐⭐⭐ | None | Fast | Medium | Heavy scale |
Fun facts about citric acid
Citric acid isn’t just a brilliant natural descaler - it shows up in some surprising parts of everyday life.
It’s in loads of foods we eat
Think Haribo (Starmix and my fave Tangfastics), Skittles, tinned tomatoes, hummus, fizzy drinks, crisps (especially salt & vinegar - like good old Walkers), pastries, fruit juices, dips and sauces. It adds tang, keeps food fresh, and stops things going brown.
It’s what makes bath bombs fizz
Citric acid reacts with bicarbonate of soda when it hits warm water, releasing carbon dioxide bubbles — that satisfying fizzy bath bomb effect is basically the same reaction happening in your kettle when limescale dissolves.
It’s made naturally through fermentation
Most commercial citric acid comes from fermenting sugars – a similar process to making soy sauce or yoghurt. It’s food-safe, clean, and widely used.
Your own body makes it
Citric acid is part of the Krebs cycle – the energy-production process inside your cells. It’s literally part of how you stay alive.
It’s incredibly safe on skin
In the small amounts used for cleaning (1–2 tablespoons dissolved in water), it’s very gentle. Getting it on your hands is fine – it might feel a bit ‘squeaky clean’, but a quick rinse is all you need.
It’s biodegradable and environmentally friendly
Unlike harsher chemical descalers, citric acid breaks down naturally and doesn’t harm waterways.
It’s gentle enough for skincare
You’ll find tiny amounts in facial toners and exfoliants to balance pH or help smooth skin.
What not to use on your kettle
A few common “cleaning hacks” are best ignored. Abrasive cleaners and scouring pads can scratch the inside of the kettle and damage the element. Bleach should never be used in any appliance that heats water. Salt is corrosive to stainless steel, and bicarbonate of soda on its own doesn’t dissolve limescale at all. Citric acid remains the safest, gentlest and most reliable option.
When to replace your kettle
Even the best descaling routine can’t rescue a kettle forever. If the heating element looks pitted or corroded, if the interior coating is peeling or bubbling, or if you still get flakes coming through even after a thorough clean, it may be time to upgrade.
A funny smell, slow boiling, or scale trapped under a concealed element are also signs the kettle is on its way out. If you do replace it, choosing a model designed for hard water will help it last longer in future.
Kettle descaling FAQs
What is the best natural product to remove limescale?
Citric acid. Because it actually breaks down the mineral deposits, it's non-toxic, gentle on surfaces, doesn't smell and is much kinder to the environment than harsh chemical cleaners.
Is limescale bad for you?
Not harmful (it’s mostly calcium and magnesium) but it can affect the taste of your tea and reduce the lifespan of your kettle.
Can I use citric acid in any kettle?
It’s safe for stainless steel, glass and most plastic kettles. Just avoid older aluminium models. Rinse and boil fresh water once afterwards.
Does reboiling water cause more limescale?
Yes. Each reboil encourages more minerals to fall out of the water and harden onto surfaces.
Does citric acid leave a taste?
Not if you rinse and reboil once.
Is it safe to boil water with citric acid?
Yes. Citric acid is used in lots of foods and drinks, so boiling it in your kettle is perfectly safe. Just pour it away afterwards and boil fresh water once before using the kettle again.
What to read next
To help keep limescale under control throughout your home, you might find these guides helpful:
If you want the easiest, safest and most natural way to descale your kettle, citric acid wins every time. It works quickly, it’s satisfying to use, and it makes a noticeable difference both to the taste of your drinks and the lifespan of your kettle. And once you’ve got a bag in the cupboard, you’ll find yourself using it all over your home to tackle limescale wherever it appears.
Your kettle — and your tea — will thank you.
Author bio: Lucinda is the founder of Hard Water Home, a UK-based blog helping households in hard water areas understand the challenges and solutions more easily — and make smarter choices for their health and home. Based in Poole, she also runs an award-winning plumbing company, giving her unique insight into how water quality affects our homes. Away from the desk, she’s happiest at the beach with her family and a good cup of coffee (minus the floaty bits!). More about us ➡
