Epsom Salts UK: 1kg Bath Salts, Independently Tested

Epsom salt isn't salt. Not the kind on your chips. It's magnesium sulfate — a different mineral that happens to share a word with sodium chloride because of a spring in Surrey, not because of any chemistry in common. What you're buying on this page is a 1kg bag of that mineral, from a UK brand that publishes the lab result instead of paraphrasing it.

Most Epsom salt on UK shelves is sold on adjectives: pure, premium, natural, relaxing. None of those words are a measurement. Ours is: 98.616% magnesium sulfate, independently tested by TTI Testing Laboratories, mercury not detected. We'd rather hand you the number than another word ending in "-ing."

Buy Epsom Salts in the UK

The Rites of Salt Epsom Bath Salts — 1kg, £7.99.

No added fragrance. No added colour. No fillers. CPSR safety-assessed for cosmetic use and notified for sale in Great Britain. This is a bath and cosmetic product — external use only, not for eating. UK delivery is £2.99, or free on orders of £18.99+.

Shop Epsom Bath Salts 1kg

What are Epsom salts?

Same four-letter word. Different chemistry.

Table salt is sodium chloride, NaCl. Epsom salt is magnesium sulfate, typically sold as the hydrated crystal MgSO₄·7H₂O. They share a name for historical reasons, not chemical ones: Epsom salt takes its name from a mineral spring in Epsom, England, where it was identified centuries ago. What's sold today — ours included — is manufactured magnesium sulfate, not anything drawn from that spring.

That distinction matters for how you use it. Our Epsom Bath Salts are a bath and cosmetic product, not a food. They are not edible salt, and we don't sell them as one.

What does our lab testing show?

Our Epsom Bath Salts are independently tested by TTI Testing Laboratories. The published result: 98.616% magnesium sulfate, with mercury not detected.

Read that second line carefully. "Not detected" means the substance wasn't found at or above the level the test method could measure. It is not the same claim as "zero," and we're not going to rewrite it as one just to make a label sound more absolute than the science behind it.

A lab report is also narrower than a marketing claim, on purpose. Our testing proves the measured composition of the sample submitted, against the specific analytes the method checks for. It doesn't prove — and we don't claim — anything about detoxification, muscle function, sleep, or any other outcome a wellness label might imply. It's a chemistry result, not a health verdict.

You don't have to take that from us. Read the source documents on our Lab Reports page, or see how we handle testing and provenance across the whole product range on The Science. If you want the longer version of what a genuine purity result should and shouldn't tell you, we've written about it directly: Are All Epsom Salts the Same? What to Check Before You Buy.

Epsom salts vs Himalayan bath salts

These get shelved next to each other and treated as interchangeable. They aren't.

Epsom salt is magnesium sulfate — one compound, sold for one purpose. Himalayan bath salt is rock salt, predominantly sodium chloride, coloured by trace constituents in the rock itself and cut into coarse crystals for bathing rather than cooking. Different mineral, different origin, different crystal.

Neither is medically superior to the other, and we're not going to tell you otherwise to move more of either one. They're two different minerals sold for the same basic ritual — a warm bath — and the honest answer to "which is better" is "depends what you're comparing them on," not a health claim dressed up as one. If you want the fuller side-by-side, we've written one: Epsom Salts vs Himalayan Bath Salts. For the pink alternative itself, see our Pink Himalayan Bath Salts UK guide.

Why formulation and evidence matter more than the label

Two pouches can both say "Epsom Salt" on the front. That doesn't mean the same thing sits inside them.

Formulation is the first fork in the road: is there anything in the pouch besides magnesium sulfate — added fragrance, added colour, anti-caking agents, filler? Ours has none of those. What's on the ingredient list is what's in the bath.

Evidence is the second fork, and the one most brands skip. "Lab-tested" printed on a pouch is a sentence. A published report with a method and a result is a document. We publish the second one. That's the difference between asking you to trust an adjective and giving you something you can actually check.

What we will claim — and what we won't

We will tell you what it is.
We will show you what was tested.
We will publish the evidence.
We will not turn a bath ingredient into a medical degree.

No detox claims. No muscle or medical outcomes attached to a mineral salt. No "100% pure" unless a report says so — ours doesn't say 100%, it says 98.616%, and we'd rather print the real number than round up.

How to use Epsom salts in a bath

Pour into a warm bath. Soak. Switch off.

That's the guidance that applies to this product — external use only, not for eating, not for any purpose beyond bathing. We haven't invented a dosage chart, a soak time, or a frequency, because none of that is something we can substantiate. Use it the way the product is intended: as a bath salt.

Why buy Epsom salts from The Rites of Salt?

Because the evidence is the pitch, not the decoration around it.

Independent testing, published rather than summarised. A specific result — 98.616% magnesium sulfate, mercury not detected — instead of an adjective. CPSR safety assessment for the UK cosmetic market, on record. A formulation with nothing added to explain away. And a brand that would rather lose a sale than invent a benefit a lab report can't back up.

Provenance with a receipt, not provenance as theatre. That's the whole pitch. This isn't a cure. It's a bath with a lab report attached.

FAQs

What are Epsom salts?

Magnesium sulfate, typically sold as the hydrated crystal MgSO₄·7H₂O. It isn't table salt, isn't sodium chloride, and our version is a bath and cosmetic product, not a food.

Are Epsom salts the same as Himalayan salt?

No. Epsom salt is magnesium sulfate. Himalayan bath salt is rock salt, predominantly sodium chloride. They're different minerals sold for the same basic ritual, not versions of the same product. See Pink Himalayan Bath Salts UK for that product's own facts.

Can Epsom salts be eaten?

Our Epsom Bath Salts are sold for bath and cosmetic use only. They are not an edible product, and we don't market or label them as one.

What does lab-tested Epsom salt mean?

It means an independent laboratory checked a sample against a defined set of measures — in our case, composition and specified heavy metals — and published a result. Ours returned 98.616% magnesium sulfate, with mercury not detected under the method used. Read the actual report on our Lab Reports page rather than a summary of it.