All Home Test Kits
Kidney & Electrolyte Home kit
Kidney health · home kit

Kidney & Electrolyte

Creatinine, eGFR and urea with sodium, potassium and chloride — how well your kidneys are filtering, and how well they are keeping your body salts in balance.

Price £88 £73.99
Covers 6 markers
Type Home kit · posted to you
Order just this kit
Blood sample, collected at home
Avoid strenuous exercise and a large meat meal for 24 hours before. Drink normally — neither more nor less than usual.
Free delivery — posted to any UK address
Results explained by our clinical team
About this test

Everything you need to know about Kidney & Electrolyte

This is the kidney check most often used in general practice, sometimes called “U&Es” (urea and electrolytes). Creatinine and eGFR show how well the kidneys are filtering, and urea adds a second measure of how they are clearing waste. Sodium, potassium and chloride are the electrolytes the kidneys control to keep your fluid balance, nerves and muscles working — including the rhythm of your heart.

It is a sensible regular check if you have high blood pressure, diabetes or heart disease, or take medicines such as blood pressure tablets, diuretics or regular anti-inflammatories that can affect the kidneys or body salts. Our clinical team explains your results and what to do next if anything is outside the range.

What's measured

What's included

6 markers in this test

Chloride Creatinine Estimated Glomerular Filtration Rate (eGFR) Potassium Sodium Urea
Who it's for

Worth considering if

  • High blood pressure, diabetes or heart disease
  • Taking blood pressure tablets, diuretics or regular anti-inflammatories
  • Training hard or sweating heavily and wanting to check your salts
  • A routine kidney check from home
Important: A home test is not a diagnosis on its own. Where something needs looking at, we tell you what it means and what to do next. If you are unwell now, please see your GP or call 111 rather than waiting for a kit.
What to expect

Your home kit

1

Order online

Add the kit to your order — several kits can go in one order — and enter your delivery address. We post it to your door as soon as your payment reaches us, with free delivery.

2

Collect your sample at home

Follow the step-by-step instructions in the box. Avoid strenuous exercise and a large meat meal for 24 hours before. Drink normally — neither more nor less than usual. Post the sample back the same day, Monday to Thursday, in the return packaging provided.

3

Results explained

Your results are released to your account with a written explanation from our clinical team.

Frequently Asked

Kidney & Electrolyte — FAQs

Why might potassium need repeating?
Potassium is released from red blood cells if they are damaged while the sample is collected or in the post, which can make a home sample read falsely high. If your potassium is raised but everything else looks as expected, our clinician may suggest a repeat before drawing any conclusions.
Can how much I drink affect the result?
Yes. Drinking a large amount of water just before collecting can dilute your sodium, and being dehydrated can raise urea and creatinine. Drink normally the day before and on the morning you collect.
How is this different from the Kidney Function Test?
The Kidney Function Test includes everything here plus albumin, calcium, magnesium and phosphate, for a broader look at kidney and mineral health.
How does the kit reach me?
We post it to your address anywhere in the UK as soon as your order is paid, and email you when it has been dispatched. Delivery is free on every home blood test kit. Everything you need to collect your sample and send it back is in the box.
How do I collect the sample?
Your kit contains everything you need and step-by-step instructions. Read them through first, collect at the time of day this test needs (see the preparation note above), label the sample and pack it in the return packaging provided.
When should I post my sample back?
On the day you collect it, Monday to Thursday, and not the day before a bank holiday — so it reaches the laboratory quickly and does not sit in the post over a weekend. A sample that arrives too old may not be able to be analysed.
Can I order several kits at once?
Yes. Use “Add to order” on each kit and then “Order” in the bar at the bottom — they go into one order and one payment and are posted together. Clinic blood tests are booked separately, because they need an appointment rather than an address.
How do I pay?
Home kit orders are paid by bank transfer. When you place your order we show our bank details and your payment reference on screen and by email, and we post your kit as soon as the payment reaches us.
How do I get my results?
Once the laboratory has analysed your sample, your results are released to your secure account with a written explanation from our clinical team, and a call where something needs talking through. Turnaround depends on the test and starts when the laboratory receives your sample.
More home test kits

Often ordered together

Add several kits to one order — one payment, posted together.

Kidney & liver Blood Urea Nitrogen (BUN) £101 £79.99
Kidney & liver Kidney Filtration Check (eGFR) £93 £74.99
Kidney & liver Kidney Function Test £89 £74.99
Kidney & liver Essential Liver £84 £69.99
Heart & metabolism Apolipoprotein Balance £125 £99.99
Vitamins & iron Calcium Blood Test £89 £69.99
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