Vitamin D Blood Test
Vitamin D Blood Test can be requested without a referral, and this overview covers what to expect. The vitamin D blood test measures the level of vitamin D in your blood. It is ordered to check for deficiency, which can affect bone health, and to monitor treatment.
- Sample type
- blood
- Category
- Vitamin & Mineral
- Turnaround
- 1-3 business days
- Price
- $118
- Referral
- Not required
The vitamin D blood test measures the level of vitamin D in your blood. It is ordered to check for deficiency, which can affect bone health, and to monitor treatment.
What it measures
- 25-hydroxyvitamin D — The main form of vitamin D in the blood; used to assess overall vitamin D status.
- 1,25-dihydroxyvitamin D — The active form; measured less often, usually for specific medical conditions.
- Calcium — Often checked alongside vitamin D because vitamin D helps regulate calcium levels.
- Phosphate — Sometimes measured because vitamin D affects phosphate balance.
- Alkaline phosphatase — A bone enzyme that may be checked if bone health is a concern.
Who it is for
A clinician may order this test if you have symptoms of deficiency, such as bone pain or muscle weakness, or if you have conditions that affect vitamin D absorption. It is also used to monitor vitamin D levels during treatment.
Preparation
No fasting is required for a vitamin D blood test. Tell your clinician about any supplements you take, as they may affect results.
Results and what they mean
Results are reported as a number, typically in nanograms per milliliter (ng/mL). Your clinician will interpret the result based on your health history and other factors. This is general information, not medical advice; discuss your results with a qualified healthcare professional.
How to order this test
- Choose the test and place a confidential order online.
- Select a certified collection site and pick a time that suits you.
- Have your specimen collected — most draws take only a few minutes.
- Review results in a secure portal, typically within 1–3 days.
Preparation, hours, and pricing vary by site; confirm details directly with the lab before your visit.
Availability by state
Direct-access online ordering for the vitamin d blood test is available in most states. It is currently unavailable in 6 states:
Everywhere else you can order confidentially and collect your sample at a certified site. Browse by state →
Frequently asked questions
Do I need to fast for this test?
No, fasting is not required. You can eat and drink normally before the test.
How long does it take to get results?
Results are usually available within 1 to 3 business days.
What can affect my vitamin D test results?
Supplements, certain medications, and the time of year can affect your levels. Tell your clinician about anything you are taking.
Is this test covered by insurance?
Coverage varies by insurance plan and medical necessity. Check with your insurance provider.