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Last updated: September 2026 · 9 minute read
Potassium citrate guide · Capsules and powder · UK
Potassium Citrate UK: The Complete Guide to Capsules and Powder
Potassium is the mineral most UK adults get least of, relative to what the body needs, and it has three authorised health claims: nervous system, muscle function and the maintenance of normal blood pressure. This guide explains what potassium citrate is, how much potassium a capsule really provides, who should not take it, and how to choose between capsules and powder.
Quick answer
Potassium citrate is the potassium salt of citric acid, the same form found in fruit and vegetables. Food-grade tri-potassium citrate is about 36% potassium, so a 1000mg capsule provides at least 358mg of potassium (18% NRV) and 1g of powder does the same. Potassium contributes to normal functioning of the nervous system, normal muscle function and the maintenance of normal blood pressure. It is a food supplement, not a medicine, and people with kidney problems or on blood pressure medicines should not take it without medical advice.
Why potassium is the mineral people forget
Ask most people to name a mineral they might be short of and they say iron, magnesium or zinc. Potassium rarely comes up, yet the NHS puts an adult's daily need at 3,500mg, and the European Food Safety Authority set its adequate intake at 3,500mg a day in its 2016 assessment. That is roughly eight bananas. Diets built on processed food, which is high in sodium and low in fruit and vegetables, tend to fall well short, a pattern Weaver's 2013 review in Advances in Nutrition describes as a "shortfall nutrient" across Western diets.
Potassium sits inside your cells, sodium sits outside, and the gradient between the two is what nerves and muscles run on. About 90% of what you eat leaves in urine, so there is no long-term store: intake matters every day, as Stone, Martyn and Weaver set out in their 2016 review.
None of that is a reason to reach for a supplement before a bag of spinach. But if you want to buy potassium citrate UK shoppers can trust, this guide tells you what to look for and what to avoid.
The three authorised health claims, and what they actually mean
In Great Britain a supplement can only carry health claims from the official register. Potassium has three. The wording on the left is fixed by law; the explanation on the right is ours.
| Authorised claim | What it means |
|---|---|
| Potassium contributes to normal functioning of the nervous system | Every nerve signal is an electrical pulse, and potassium moving in and out of nerve cells is what makes the pulse. Keep potassium in its normal range and the signalling runs as it should. This is a claim about maintaining normal function, not about improving it. |
| Potassium contributes to normal muscle function | Muscle fibres contract when an electrical signal reaches them, and that signal depends on potassium and sodium swapping places across the cell membrane. The heart is a muscle too. Again: normal function, kept normal. |
| Potassium contributes to the maintenance of normal blood pressure | The body balances sodium and potassium against each other. Adequate potassium helps the kidneys keep that balance, which is part of how blood pressure stays in its normal range. The word that matters is maintenance. This claim is about keeping normal blood pressure normal. It is not a claim to lower raised blood pressure, and no food supplement can lawfully make that claim. |
A line we will not cross
You will see potassium sold online as a blood pressure remedy. That is a medicinal claim and it is unlawful. If you have high blood pressure, speak to your GP. If you are already on blood pressure medication, read the safety section below before you go any further, because potassium supplements and some of those medicines do not mix.
Why citrate, not chloride?
Potassium comes in several salt forms. Potassium chloride is the one used as a salt substitute and in many cheap supplements. Potassium citrate is the form found in fruit and vegetables, where potassium arrives bound to organic acids. Weaver's review notes that the organic-anion forms, such as citrate, are the ones associated with the wider benefits seen in fruit-and-vegetable diets, whereas chloride is not.
The form in food
Fruit and vegetables supply potassium as citrate and malate, not chloride. Citrate is the salt that matches what a diet high in produce delivers.
Citrate is metabolised to bicarbonate
Once absorbed, the citrate part is used up by the body and does not add to the acid load the way chloride does. That is a compositional fact, not a health claim.
Milder on the stomach
Potassium chloride tablets are known for stomach irritation. Citrate, taken with food and water, is generally better tolerated.
Taste
Potassium chloride tastes bitter and metallic, which is why salt substitutes are unpopular. Citrate is salty-sour, and in a capsule you taste nothing.
The numbers most sellers leave out
A label that says "1000mg potassium citrate" is telling you the weight of the salt, not the potassium. Tri-potassium citrate monohydrate is 35.79% to 36.16% potassium by weight, so 1000mg of it provides 358 to 362mg of potassium. We declare the lower figure, 358mg (18% NRV), so it holds for every batch. Any label declaring "1000mg potassium" from a 1000mg citrate capsule has got its maths wrong by nearly three times.
Our material · supplier technical dossier
What is in a Charge Products potassium citrate capsule
99%+
assay, anhydrous basis
358mg
potassium per 1000mg
18%
NRV per capsule
E332(ii)
tri-potassium citrate
0
fillers, flow agents
WADA
no banned substances
Tri-potassium citrate monohydrate, C6H5O7K3·H2O, made to the British Pharmacopoeia and EU food additive specification. Supplied through a UK ingredient house holding BRC Food Safety accreditation. The dossier confirms no declarable allergens present or handled at the site, non-GM, not irradiated, within pesticide residue limits, TSE/BSE free, and free of nandrolone, its precursors and IOC/WADA banned substances. The source is synthetic, citric acid reacted with potassium hydroxide, so we do not call it natural. Trade buyers can request the certificate.
Read this before you buy any potassium supplement
Potassium is treated differently from other minerals, and for good reason. Healthy kidneys clear excess potassium within hours. Kidneys that are not working well cannot, and some common medicines hold potassium in the body. Too much potassium in the blood affects the heart's rhythm. That is why potassium supplements come with a longer caution list than magnesium or zinc, and why we sell ours with one capsule a day, never more.
Do not take potassium supplements without medical advice if you
have any kidney impairment · take an ACE inhibitor (names ending in -pril) · take an ARB (names ending in -sartan) · take a potassium-sparing diuretic such as spironolactone or amiloride · take any potassium-containing medicine or use a potassium salt substitute · have a heart condition, diabetes or adrenal insufficiency · have a stomach ulcer or slowed gut transit.
For everyone else
Take it with food and a full glass of water, never on an empty stomach. One capsule a day. Not suitable for under 18s, or during pregnancy or breastfeeding without advice. Food supplement, not a medicine.
Capsules or powder: which should you choose?
We sell the same tri-potassium citrate two ways. The right one depends on how you want to use it, not on quality, because the material is identical.
Potassium Citrate Pro 1000mg capsules · pouch or capsule close-up
Potassium Citrate Pro 1000mg Capsules
One capsule = 1000mg tri-potassium citrate = 358mg potassium (18% NRV). Size 00 vegan HPMC shell, salt only, no fillers. Fixed dose, no taste, no scales. Packs from 30 to 500 capsules, from £7.99, with two extra capsules in every pack.
Choose capsules if: you want a set daily amount with no measuring, you dislike the taste, or you are buying for the first time.
View capsules on chargeproducts.co.ukView on eBay
Tri-Potassium Citrate Powder · pouch or crystal close-up
Tri-Potassium Citrate Powder
The same E332(ii) material, loose. 500mg = 179mg potassium (9% NRV); 1g = 358mg (18% NRV). Dissolves fully in water. Lowest cost per gram and the format trade buyers and formulators use. Needs milligram scales, because kitchen scales cannot weigh 500mg accurately.
Choose powder if: you want to start at 500mg and adjust, you mix it into a drink, or you buy in bulk.
View powder on chargeproducts.co.ukStill undecided? Our powder vs capsules comparison goes through cost per serving, taste and dosing in more detail.
| Pro 1000mg capsules | Powder | |
|---|---|---|
| Material | Tri-potassium citrate monohydrate, E332(ii) | Identical |
| Potassium per serving | 358mg (18% NRV) per capsule | 179mg per 500mg · 358mg per 1g |
| Daily amount | 1 capsule | 500mg to 1g |
| Taste | None | Salty-sour, dissolved in water |
| Measuring | None needed | Milligram scales |
| Shell | Vegan HPMC, size 00 | None |
| Best for | Daily routine, first-time buyers | Adjustable dose, bulk, formulating |
How to take potassium citrate
- Capsules: one a day with a meal and a full glass of water.
- Powder: weigh 500mg for the first week, dissolve in water, take with food. Move to 1g if you wish. Do not exceed 1g a day.
- Never on an empty stomach, and never with other potassium supplements or salt substitutes.
- Check the caution list above once more if you take any regular medication.
3
authorised claims
358mg
potassium per capsule
99%+
assay
0
fillers
164K+
verified sales
2016
trading since
Where to buy potassium citrate UK
You can buy potassium citrate UK-wide from Charge Products in either format: Potassium Citrate Pro 1000mg capsules from £7.99, or tri-potassium citrate powder in bulk sizes. If you are asking where to buy potassium citrate UK shoppers can trust on a marketplace, the capsules are also on our eBay store, where Charge Products holds 99.7% positive feedback across 164,000+ sales. However you order potassium citrate UK stock leaves Southend-on-Sea the same day before 3:30pm Monday to Friday, with free UK delivery over £10 and 30-day returns on sealed packs. Trade and wholesale enquiries go through the contact page.
Ready to try it?
One capsule a day, 358mg of potassium, nothing else in the shell. 5 Star Food Hygiene Rating · same-day dispatch · UK supplier since 2016.
Potassium Citrate Pro 1000mg CapsulesTri-Potassium Citrate PowderPotassium citrate: frequently asked questions
What is potassium citrate?
Potassium citrate is the potassium salt of citric acid. The food-grade form is tri-potassium citrate monohydrate, additive number E332(ii), which is about 36% potassium by weight. It is the form of potassium that occurs naturally in fruit and vegetables.
How much potassium is in a 1000mg capsule?
A 1000mg tri-potassium citrate capsule provides at least 358mg of potassium, which is 18% of the nutrient reference value. The powder provides 179mg per 500mg and 358mg per 1g.
Which is better, potassium citrate capsules or powder?
They contain the same tri-potassium citrate. Capsules give a fixed 358mg dose with no taste and no scales. Powder costs less per gram and dissolves in water, but has a salty-sour taste and needs milligram scales. First-time buyers usually start with the capsules.
Can I take potassium citrate every day?
One 1000mg capsule a day, or 500mg to 1g of powder, taken with food and a full glass of water, is the intake stated on the packs. Do not exceed it without medical advice.
Who should not take potassium supplements?
Anyone with kidney impairment, and anyone taking ACE inhibitors, ARBs, potassium-sparing diuretics, potassium-containing medicines or salt substitutes, should not take potassium supplements without medical advice. The same applies to heart conditions, diabetes, adrenal insufficiency, stomach ulcers or slowed gut transit.
Does potassium citrate lower blood pressure?
No food supplement can claim that. The authorised claim is that potassium contributes to the maintenance of normal blood pressure. If your blood pressure is raised, that is a matter for your GP, not a supplement.
Is potassium citrate natural?
No. Food-grade potassium citrate is made by reacting citric acid with potassium hydroxide. It is chemically identical to the potassium citrate in fruit, but it is a manufactured ingredient and we describe it as one.
Is it suitable for tested athletes?
The supplier dossier confirms no IOC or WADA banned substances and no nandrolone or precursors, and no allergens are declared or handled at the manufacturing site.
References
Educational context only. The only health claims made for our products are the three authorised claims above.
1. Weaver CM. Potassium and Health. Adv Nutr. 2013;4(3):368S-377S. Review. PubMed 23674806
2. Stone MS, Martyn L, Weaver CM. Potassium Intake, Bioavailability, Hypertension, and Glucose Control. Nutrients. 2016;8(7):444. Review. PubMed 27455317
3. EFSA NDA Panel. Dietary reference values for potassium. EFSA Journal. 2016;14(10):4592. Scientific opinion. doi.org/10.2903/j.efsa.2016.4592
Disclaimer: Potassium citrate is a food supplement, not a medicine. Not intended to diagnose, treat, cure or prevent any disease, including high blood pressure. The health claims above are the authorised Great Britain claims for potassium; the blood pressure claim concerns the maintenance of normal blood pressure only. Do not take potassium supplements if you have kidney impairment or take ACE inhibitors, ARBs, potassium-sparing diuretics or potassium-containing medicines without medical advice. Not suitable for under 18s, or during pregnancy or breastfeeding without advice. Do not exceed the stated daily amount. Food supplements should not be used as a substitute for a varied, balanced diet and a healthy lifestyle. Keep out of reach of children. Charge Products is a trading name of Big Idea Services Ltd, Company No. 11645389, Unit 1, 8 Towerfield Road, Towerfield Industrial Estate, Southend-on-Sea, Essex SS3 9QE.
