Phosphate in Urine Test
A phosphate in urine test measures the amount of phosphate in your urine over 24 hours. It helps check how well your kidneys and parathyroid glands are working and can help diagnose kidney stones or other conditions.
What this test measures
This test measures the amount of phosphate (a form of phosphorus) in a urine sample collected over 24 hours. Phosphate is an electrolyte that helps build bones, make energy, and support nerve and muscle function.
What your results mean
Reference ranges vary by laboratory and by your age and sex. MedlinePlus does not publish a single normal range for this test — always read your result against the range printed on your own lab report and discuss it with your provider.
Higher-than-normal results
High phosphate/phosphorous levels in your urine may mean you have kidney disease that affects your kidneys' ability to hold on to phosphate, or hyperparathyroidism (too much parathyroid hormone).
Lower-than-normal results
Low phosphate/phosphorous levels in your urine may mean you have kidney disease that affects your kidneys' ability to get rid of extra phosphate, or hypoparathyroidism (too little parathyroid hormone).
Frequently asked questions
What is a phosphate in urine test?
It measures the amount of phosphate in your urine over 24 hours. Phosphate contains the mineral phosphorus and is an electrolyte that helps control fluid balance, build bones, and support nerves and muscles.
Why might I need this test?
Your provider may use it to understand the cause of high or low phosphate in your blood, find out if too much phosphate in urine is causing kidney stones, or diagnose kidney or parathyroid gland problems.
How is the test done?
You collect all your urine over a 24-hour period in a container provided by your lab. Follow your provider's instructions carefully.
What do high results mean?
High phosphate levels in urine may mean you have kidney disease that loses too much phosphate or hyperparathyroidism (too much parathyroid hormone).
What do low results mean?
Low phosphate levels in urine may mean you have kidney disease that holds onto phosphate or hypoparathyroidism (too little parathyroid hormone).
Related lab tests
Sources
- MedlinePlus: Phosphate in Urine — NIH MedlinePlus
Last updated . Information is aggregated from official public sources and is not a substitute for professional medical care.