How to Test Cortisol Levels at Home in UK

As a doctor, I meet many patients who feel tired, stressed, or unable to sleep properly. Often, they worry their symptoms may be linked to cortisol, the body’s main stress hormone. The good news is that you can check your cortisol levels from home in the UK with simple, reliable methods. Let me guide you step-by-step so you understand what to do and when to speak to a healthcare professional.

What Is Cortisol and Why Should You Test It?

Cortisol helps your body manage stress, control blood sugar, support immunity, and maintain normal sleep patterns. However, when cortisol becomes too high or too low, you may notice:

  • Constant tiredness
  • Trouble sleeping
  • Weight gain around the belly
  • Mood swings
  • Anxiety
  • Low energy in the morning
  • Unexplained headaches

Testing at home is a good first step if you want to understand how your body is reacting to stress.

Home Cortisol Testing Options in the UK

In the UK, you can check cortisol from home using:

1. Saliva Test Kits (Most Common)

This is the most recommended at-home method. You collect a small saliva sample at different times of the day because cortisol changes throughout the day. So, you have to order more than 1 panel saliva kit.

How it works:

  1. You receive a kit by post
  2. You take saliva samples (usually morning, afternoon, evening)
  3. You send the samples back to the lab
  4. You get your results online

This gives a clear picture of your cortisol pattern.

2. Finger-Prick Blood Test Kits

These tests measure total cortisol in the blood. They’re helpful, but they capture only a single moment, not the full daily pattern.

How it works:

  1. Use a lancet (small needle)
  2. Collect a few drops of blood
  3. Send the sample to the partner lab
  4. Get results by email or app

3. Urine Test Kits (Less Common at Home)

Some UK labs provide 24-hour urine collection kits. These tests show how much cortisol your body produces throughout the day.

This method is usually used when doctors want a more detailed hormonal picture, but can still be done at home.

How to Use a Cortisol Home Test Kit

Here is a simple guide I share with my patients:

1. Order a Reputable Kit

Choose a trusted UK provider that works with accredited laboratories (look for UKAS accreditation). Avoid unknown brands with unclear instructions.

2. Follow Timing Instructions Carefully

Cortisol is highest in the morning and lowest at night, and take samples exactly when the kit tells you to.

3. Avoid These Before Testing

For accurate results:

  • No food, smoking, or caffeine 30 minutes before saliva sampling.
  • Avoid heavy exercise for at least 1 hour.
  • Do not take steroid medicines unless your doctor approves.
  • Keep stress low on the test day.

4. Collect the Sample Properly

Follow each step slowly and do not rush and seal the sample correctly and place it in the provided envelope.

5. Post the Sample on Time

Send your kit back the same day, and most UK providers use priority return envelopes for faster processing.

6. Read Your Results

Results usually include:

  • Morning cortisol
  • Afternoon cortisol
  • Evening cortisol
  • Your overall cortisol rhythm
  • Clear explanations of each reading

What Do Your Results Mean?

Here’s how I help my patients understand their numbers:

High cortisol may cause:

  • Trouble sleeping
  • Anxiety
  • Weight gain
  • Feeling “wired but tired”

Low cortisol may cause:

  • Constant exhaustion
  • Dizziness
  • Sugar cravings
  • Morning fatigue

If your results are outside the normal range, it is important to discuss them with a doctor or endocrinologist. Cortisol imbalance may relate to conditions such as adrenal fatigue, chronic stress, thyroid disorders, or Addison’s/Cushing’s disease.

When You Should See a Doctor Immediately

Please contact a GP or seek urgent care if you experience:

  • Very low blood pressure
  • Severe dizziness
  • Sudden weight loss
  • Dark patches on the skin
  • Unexplained vomiting
  • Severe weakness

These symptoms may suggest a serious adrenal issue.

Lifestyle Changes to Support Healthy Cortisol

While you await results or recover from stress-related issues, simple habits help:

  • Sleep 7–8 hours
  • Reduce caffeine
  • Mild morning sunlight exposure
  • Daily walking or light exercise
  • Deep-breathing exercises
  • Balanced meals with enough protein

Final Advice From Your Doctor

Testing your cortisol levels at home in the UK is safe, simple, and often the first step to understanding your stress health. If you feel your results are concerning or your symptoms are getting worse, please speak to a healthcare professional. Early guidance can prevent long-term hormonal and adrenal issues.

Back to blog

Featured collection

View all