All Home Test Kits
Blood Urea Nitrogen (BUN) Home kit
Kidney health · home kit

Blood Urea Nitrogen (BUN)

Measures urea — the main waste product left when your body breaks down protein — and reports it as blood urea nitrogen (BUN), a simple check on how your kidneys are clearing waste.

Price £101 £79.99
Covers 2 markers
Type Home kit · posted to you
Order just this kit
Blood sample, collected at home
No fasting needed. Drink normally and avoid an unusually large high-protein meal the evening before.
Free delivery — posted to any UK address
Results explained by our clinical team
About this test

Everything you need to know about Blood Urea Nitrogen (BUN)

When your body breaks down protein, the leftover nitrogen is turned into urea by the liver and filtered out of the blood by the kidneys. Measuring how much urea is in your blood — reported as urea, and as blood urea nitrogen (BUN), the figure used in many international references — gives a quick read on that clearing process.

Urea is a useful first look rather than the full picture. It rises with dehydration, a high-protein diet, some medicines and bleeding in the gut as well as with reduced kidney function, and it can be low with a low-protein diet or liver problems. That is why it is best read alongside creatinine and eGFR — if you want a proper kidney check, the Kidney Function Test covers all three and the main body salts.

What's measured

What's included

2 markers in this test

Blood Urea Nitrogen (BUN) Urea
Who it's for

Worth considering if

  • A simple check on kidney clearance as part of a routine health check
  • A high-protein diet or heavy training, and wanting to see the effect
  • Following up a previous urea result
  • Taking a medicine that can affect the kidneys — alongside, not instead of, your usual monitoring
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. No fasting needed. Drink normally and avoid an unusually large high-protein meal the evening before. 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

Blood Urea Nitrogen (BUN) — FAQs

What is the difference between urea and BUN?
They measure the same thing. UK laboratories usually report urea in mmol/L; BUN expresses the nitrogen part of urea in mg/dL, the unit common in the US. Your report includes both so you can compare it with other results.
Can diet and hydration affect the result?
Yes. Being dehydrated or eating a lot of protein can push urea up; a low-protein diet can bring it down. Drink normally the day before and avoid an unusually large high-protein meal the evening before you collect.
Is this enough to check my kidneys?
It is a starting point. Creatinine and eGFR are the main measures of kidney filtration, so for a proper kidney check choose the Kidney Filtration Check (eGFR), Kidney & Electrolyte or the Kidney Function Test.
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 Kidney Filtration Check (eGFR) £93 £74.99
Kidney & liver Kidney Function Test £89 £74.99
Kidney & liver Kidney & Electrolyte £88 £73.99
Kidney & liver Essential Liver £84 £69.99
Heart & metabolism Apolipoprotein Balance £125 £99.99
Vitamins & iron Calcium Blood Test £89 £69.99
All Home Test Kits