Skip to content

24-Hour Urine Free Cortisol Mass Concentration

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

This test measures the amount of cortisol (a natural steroid hormone) excreted in your urine over 24 hours. It helps assess how well your body produces cortisol, which is important for managing conditions like Cushing’s syndrome or adrenal insufficiency.

Quick summary

["This test helps doctors check if your cortisol levels are too high or too low over time."]

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

Key facts at a glance

LOINC
1396-1
Short code
Cortis F pre 2 mg Dex high 24h Ur-mCnc
Synonyms
Cortis F pre 2 mg Dex high 24h Ur-mCnc
Category
hormone
Sample
urine
Container
Sterile urine container
Units
N/A
Ref low
20
Ref high
400
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
82670
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 Is Done

Your doctor may recommend this test if they suspect conditions like Cushing’s syndrome (too much cortisol) or adrenal gland issues. It’s particularly useful for diagnosing problems that aren’t easily detected by blood tests alone.

How the Test Works

You’ll collect all your urine for a full 24-hour period, typically starting right after you wake up. The sample is then sent to a lab for analysis to measure cortisol levels in your urine.

What to Expect Before the Test

No special preparation is needed, but you should drink enough fluids to produce urine throughout the day. Avoid taking any medications that might affect cortisol levels without consulting your doctor.

What to Expect During the Test

You’ll collect urine in a special container every time you urinate, including during the night. The test requires precise timing to ensure accurate results.

Reference range

Premenopausal: 20-400 pg/mL; Postmenopausal: <30 pg/mLN/A

Specimen: urine

No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Free Cortisol Urine Test

Frequently asked questions

Why might my doctor order this test?
Your doctor may order this test if they suspect hormonal imbalances, such as Cushing’s syndrome or adrenal gland disorders, that affect cortisol levels. It helps confirm or rule out conditions that require long-term monitoring.
How long will I need to collect urine for this test?
You’ll need to collect all your urine for a full 24-hour period, starting right after waking up. This includes urine from the first morning void until the same time the next day.
What if I miss any urine during the collection period?
If you miss any urine, you should restart the collection process immediately. It’s important to follow the full 24-hour period to get accurate results.
  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