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Urine Total and Free Protein (Urine Protein Analysis)

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

This test measures the total and free protein levels in your urine, which can help identify kidney function or conditions like proteinuria.

Quick summary

["Your urine protein levels may signal kidney health or other health concerns."]

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

Key facts at a glance

LOINC
104657-2
Short code
Sialate free and total pnl Ur
Synonyms
Sialate free and total pnl Ur
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
44
Ref high
147
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
84075
SNOMED
27550007
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Is Done

Doctors may order this test to check for signs of kidney disease, such as excessive protein loss in urine, or to monitor conditions like diabetes or high blood pressure that can affect kidneys. It can also help diagnose other conditions like kidney stones or certain infections.

What to Expect Before the Test

No special preparation is needed. You’ll provide a urine sample in a clean container, typically collected in the morning. Avoid excessive protein-rich foods or certain medications for 24 hours before testing if instructed by your doctor.

How the Test Works

Your urine sample is analyzed to measure total protein (including albumin and other proteins) and free protein (albumin specifically). The results help determine if protein is present in abnormal amounts, which may indicate kidney issues or other health problems.

Possible Results and Interpretation

Higher-than-normal protein levels in urine may signal kidney damage, inflammation, or other health conditions. Lower-than-normal levels may be normal, but further evaluation could be needed if your doctor suspects a hidden issue.

Reference range

Adult: 44-147 U/LN/A

Specimen: serum

No special preparation required. Avoid fatty meals before the test if possible.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: Understanding Protein in Urine

Short name

Urine Protein Test

Frequently asked questions

What causes protein in urine?
Protein in urine can result from kidney problems (e.g., glomerulonephritis), infections, high blood pressure, diabetes, or certain medications. Some people may also have genetic conditions or reactions to stress or exercise that temporarily increase protein levels.
How often should I get this test?
Your doctor will determine how often you need this test based on your health condition, symptoms, and medical history. Regular monitoring may be recommended if you have kidney disease, diabetes, or high blood pressure.
Can diet affect urine protein test results?
Yes, certain diets (like very high-protein diets) or foods (e.g., asparagus, which can cause mild proteinuria) may temporarily affect results. Follow your doctor’s instructions on dietary restrictions if applicable.
  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