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24-Hour Free Cortisol in Urine (24h Free Cortisol Urine)

Published: August 9, 2026Updated: August 16, 2026

This test measures the amount of cortisol (a natural steroid hormone) that appears in your urine over a 24-hour period. It helps assess how well your body produces and regulates cortisol.

Quick summary

["Helps diagnose adrenal gland disorders and cortisol imbalance."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
34909-2
Short code
Cortis F 24h Ur HPLC-mCnc
Synonyms
Cortis F 24h Ur HPLC-mCnc
Category
hormone
Sample
urine
Container
Sterile urine container
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
hplc
Specimen volume
10 mL
Stability
Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–24 hours
Order
routine

Why This Test Matters

Cortisol is a hormone produced by your adrenal glands, which sit on top of your kidneys. It plays a key role in managing stress, immune response, and metabolism. Free cortisol in urine reflects your body’s natural cortisol levels over a full day, which can be affected by conditions like Cushing’s syndrome or adrenal insufficiency.

How the Test Works

You’ll collect all your urine for a full 24 hours, typically starting and ending at the same time each day. The sample is then sent to a lab for analysis using high-performance liquid chromatography (HPLC), which separates and measures cortisol in your urine.

What to Expect Before the Test

No special preparation is needed, but you may be asked to avoid certain medications that could affect cortisol levels, such as some steroids or blood pressure medications. Always inform your healthcare provider about all medications you’re taking.

What to Expect During the Test

You’ll collect your urine in a container provided by your healthcare team. It’s important to empty your bladder completely at the start and end of the 24-hour period, and discard the first morning urine. Store the remaining urine in a cool place until you return it to the lab.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Urine Free Cortisol (24h)

Frequently asked questions

How long does it take to get results?
Results are typically available within 1 to 2 weeks, depending on the lab’s processing time. Your healthcare provider will discuss the results with you during your follow-up appointment.
Can I take my usual medications before this test?
Yes, but always inform your healthcare provider about all medications you’re taking, including over-the-counter drugs and supplements. Some medications may affect cortisol levels.
What if I miss any urine during the 24-hour collection?
If you miss any urine, you’ll need to restart the collection from the beginning. It’s important to complete the full 24 hours to get an accurate reading. If you’re unsure, contact your healthcare provider for guidance.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy