How to use citric acid to remove limescale in your home — kettle, washing machine & more
- 58 minutes ago
- 8 min read
In hard water areas, limescale isn’t just a cleaning issue — it’s a chemistry issue. And the most effective natural solution isn’t vinegar or lemon.
It’s citric acid.
I’ve tried all the recommended natural methods over the years. Vinegar works, but the smell makes it a last resort. Lemon juice is nicer, but rarely strong enough for stubborn limescale. Once I switched to citric acid, though, I was completely converted.
It reacts directly with limescale, dissolves it quickly, and does the job without harsh fumes or smells. One tub replaces multiple cleaning products — and works in kettles, toilets, shower heads, dishwashers and more.
In this guide, I’ll show you exactly how to use citric acid throughout your home, why it works so well in hard water areas, and where not to use it.
Why citric acid works so well on limescale
Limescale is mainly calcium carbonate — the mineral left behind when hard water is heated or evaporates. Citric acid works because it reacts directly with calcium carbonate and dissolves it into a soluble form that can be rinsed away.
In simple terms: It doesn’t scrub limescale off — it breaks it down chemically.
It’s also:
Biodegradable
Naturally made (produced through fermentation of sugars)
Odourless
Very cost effective
Easily available on Amazon
For hard water homes, it’s one of the most effective low-cost tools you can keep on hand.
Quick guide
How much citric acid should you use to descale?
One of the most common questions we get is: how much citric acid do you actually need? Here's what we recommend:
Kettle: 1–2 tablespoons in half a kettle of water
Toilet: 2–3 tablespoons directly into the bowl
Washing machine: 3–4 tablespoons in the drum on a hot empty cycle
Dishwasher: 3–4 tablespoons in the base, run a hot cycle
Shower head soak: 2–3 tablespoons in a bowl of warm water
Spray solution: 1–2 tablespoons per 500ml warm water
As a basic rule, use the lower amount for light, regular maintenance and the higher amount for more stubborn limescale. In hard water areas, lighter, more regular treatments work better than waiting for heavy build-up.
Where to buy citric acid
You can find food-grade citric acid on Amazon and sometimes in larger supermarkets. We like Aksoy's 1.25kg RRP £6 on Amazon ↗ it's often on offer, which makes it a great value option.
How to use citric acid to remove limescale around your home
How to descale a kettle with citric acid
Limescale in your kettle doesn’t just look unpleasant — it makes the element work harder, increases energy use, and can shorten the lifespan of the kettle. Even a thin layer acts like insulation, slowing down boiling and shedding flakes into drinks.
Regular light descaling keeps your kettle efficient, quieter, and your tea flake-free.
Method:
Fill kettle halfway with water
Add 1–2 tablespoons citric acid
Boil
Leave 15–20 minutes
Rinse and boil fresh water once before use
In very hard water areas, every 2–4 weeks works well.
I've tested this method repeatedly in my own hard water home in Dorset, and it's a winner every time. If you want to see exactly how effective it is, take a look at our full guide on using citric acid to remove kettle limescale.
Can citric acid be used in a washing machine?
Yes — and it’s one of the safest natural ways to descale one.
Hard water leaves mineral deposits inside the drum, heating element and pipework. Over time this can reduce efficiency, contribute to musty smells as dirt gets trapped and affect washing performance.
How to clean a washing machine with citric acid
Add 3–4 tablespoons directly into the empty drum
Run a hot cycle (60–90°C)
No laundry inside
Repeat every 1–3 months depending on water hardness.
It won’t foam like vinegar and doesn’t leave a smell. When used occasionally at the recommended amounts, citric acid is generally safe for washing machine components, including rubber seals and plastic parts — just avoid using it too frequently or in very strong concentrations.
How to descale a dishwasher
Limescale affects spray arms and heating elements, reducing cleaning power and leaving glassware cloudy.
Method:
Empty dishwasher
Add 3–4 tablespoons citric acid into the base
Run a hot cycle
Simple, effective maintenance.
How to remove limescale from toilets
Hard water leaves rings at the waterline and stubborn mineral stains that brushing alone won’t shift. Citric acid is especially good here because it can sit and work overnight.
Method:
Pour warm water into the toilet bowl
Add 2–3 tablespoons of citric acid
Leave it to sit for at least 1 hour
For heavy limescale leave overnight
Brush and flush
Repeat for heavier build-up.
If you want to find out how to remove limescale from the toilet rim and see exactly how effective this method it is, take a look at our full guide on using citric acid to remove toilet limescale.
How to descale a shower head
Limescale blocks the tiny nozzles in shower heads, reducing pressure and causing water to spray unevenly. Over time, it can make the shower feel weaker than it actually is. Descaling restores flow and improves your shower experience instantly.
Method:
Remove head if possible
Soak in warm water with 2–3 tablespoons citric acid
Leave 30–60 minutes
Rinse thoroughly
If fixed in place, tie a bag of solution around it.
Did you know hard water could be affecting your skin and hair?
The minerals that cause limescale don’t just build inside your showerhead — they can leave skin feeling tight and hair dry or dull too. That’s why many people are switching to a filtered shower head for hard water to help improve how their water feels day to day.
Shower screens, taps and chrome fittings
Visible limescale makes bathrooms look dirty even when clean. A simple citric acid solution can get them sparkling again.
Method:
Mix 1–2 tablespoons in 500ml warm water and add a small drop of washing-up liquid to help lift grime
Apply with a cloth or spray bottle, leave a few minutes
Rinse thoroughly and dry with a towel to prevent fresh marks forming
Citric acid vs vinegar: are they the same?
No — they’re not the same. Vinegar contains acetic acid, usually at around 5% strength in standard white vinegar. That means it’s already diluted in water.
Citric acid, on the other hand, is sold as a powder or fine granules. In pure form, it’s close to 100% citric acid — you then dissolve it in water to whatever strength you need. That’s why it can be more versatile: you control the concentration depending on the job.
In practice:
Citric acid is often stronger and more effective on heavy limescale
It has little to no smell
It’s easier to store long-term without going off
It doesn’t leave that “chip shop” scent in your kitchen
Vinegar absolutely works — but for regular hard water homes, citric acid tends to be more pleasant and effective to use.
Will citric acid stop limescale?
Citric acid reacts with calcium carbonate and dissolves it. That’s exactly why it’s effective in kettles, toilets and appliances.
What it doesn’t do is remove hardness minerals from your water permanently. It removes existing build-up — new scale will form again when water evaporates. The most effective way to eliminate limescale from your home permanently is to install a water softener.
Will citric acid damage chrome?
When diluted and used briefly, citric acid is generally safe on chrome fittings. The key is not to leave strong solutions sitting on the surface for long periods. Always rinse thoroughly afterwards and avoid abrasive scrubbing. If you’re unsure, test a small hidden area first before applying more widely.
Where not to use citric acid
Citric acid should not be used on natural stone such as marble or granite, as acids can permanently etch the surface. It’s also best avoided on unsealed grout, bare aluminium and delicate enamel finishes.
Like all acids, it works brilliantly when used correctly — but it needs to be used thoughtfully on sensitive materials.
Is citric acid safe to use at home?
When used diluted and rinsed properly, yes. Most citric acid sold for household use is food-grade, meaning it’s safe enough to be used in food preparation at lower concentrations — which gives many people extra reassurance.
Store it away from children and avoid inhaling the powder when measuring. It’s still an acid — just a relatively mild, naturally derived one.
How much does it cost to use?
One of the biggest advantages of citric acid is how economical it is.
Using Aksoy's £6 1.25kg bag of citric acid as an example, if you descaled your kettle, toilet, washing machine, dishwasher and shower head once every month, it would cost roughly £1.37 per month.
That bag would last around four to five months in a typical hard water home. Compared to branded descalers, specialist tablets or the cost of replacing appliances early due to scale damage, it’s one of the most cost-effective ways to stay on top of limescale.
Are you a citric acid convert?
If you live in a hard water area and want one natural product that genuinely tackles limescale, citric acid is hard to beat.
It won’t eliminate hard water permanently. But for keeping kettles efficient, toilets fresh, appliances clean and bathrooms looking good — it’s one of the smartest low-cost upgrades you can make.
FAQs: using citric acid for limescale in hard water areas
Does citric acid remove limescale?
Yes. Citric acid reacts directly with calcium carbonate — the main component of limescale — and dissolves it so it can be rinsed away. It’s effective in kettles, toilets, washing machines, dishwashers and on taps. It removes existing build-up, but it doesn’t stop new limescale forming in hard water areas.
How much citric acid do you need to descale a kettle?
For most kettles, 1–2 tablespoons of citric acid in half a kettle of water is enough. Boil, leave for 15–20 minutes, then rinse and boil fresh water once before use.
Can citric acid be used in a washing machine?
Yes. Citric acid can safely be used to descale a washing machine when used occasionally at the correct amount. Add 3–4 tablespoons to the empty drum and run a hot cycle (60–90°C). It helps remove mineral build-up and reduce odours.
Is citric acid better than vinegar for limescale?
Both work, but many people prefer citric acid. It’s often stronger on heavy limescale and doesn’t have a strong smell like vinegar. It’s also easier to store long term in powder or granule form.
Will citric acid damage chrome or bathroom fittings?
When diluted and used briefly, citric acid is generally safe on chrome. Avoid leaving strong solutions sitting on the surface, always rinse thoroughly, and test in a hidden area first if unsure.
Is citric acid safe to use at home?
Yes — when diluted properly and rinsed after use. Most household citric acid is food-grade, meaning it’s safe for use around food preparation at lower concentrations. Store safely and avoid inhaling the powder when measuring.
Author bio: Lucinda Smalley is the founder of Hard Water Home, a UK-based consumer site helping households in hard water areas understand the challenges and solutions more easily — and make smarter choices for their health and homes. Based in Poole, she also co-runs an award-winning plumbing company, giving her first-hand insight into how water quality affects everything from appliances to skin and hair. When she’s not writing, she’s happiest at the beach with her family and a good cup of coffee (minus the floaty bits!). More about us ➡
