Vitamin B12 levels: what's normal, high and low
A vitamin essential for nerve function and red blood cell formation. Found in animal foods.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
The short answer
Vitamin B12 is measured with a standard blood draw; no fasting is needed. A typical reference range is 200 – 1100 pg/mL. At TestWell it's $25.99 all-in as Vitamin B12, results in 2–4 business days, drawn at Quest or Labcorp. An out-of-range result is a prompt to look closer, not a diagnosis.
- Units
- pg/mL
- Sample
- Blood draw
- Fasting
- Not required
- Results
- 2–4 business days
- Price
- $25.99
- Labs
- Quest or Labcorp · BioReference in NY/NJ
Vitamin B12 Reference Range
These are the typical adult reference ranges used by major US labs. Your report will include the specific range used by the lab that processed your sample.
| Population | Range |
|---|---|
| age 18+ | 200 – 1100 pg/mL |
Reference ranges are educational. Always interpret your result with the specific range printed on your lab report and discuss anything outside the range with a clinician.
What your Vitamin B12 result may mean
Common in vegetarians/vegans, older adults, and people on metformin or acid-suppressing medications. Can cause anemia and neurological symptoms.
What a low Vitamin B12 means: causes, symptoms, next steps →Educational only — not a diagnosis. Many factors can influence a single result. Discuss anything that concerns you with a healthcare provider.
How do you get a Vitamin B12 test?
Order online, a licensed physician reviews the requisition, and you walk into a nearby lab for the draw. Vitamin B12 is available on its own or inside these panels — panels cost less per marker when you want the fuller picture.
| Option | Includes | Price |
|---|---|---|
| Vitamin B12 | This marker only | $25.99 |
| Baseline Anemia Panel | 5 tests | $74.99 |
| Comprehensive B12 Deficiency Panel | 3 tests | $79.99 |
| Basic Vitamin Deficiency Panel | 3 tests | $89.99 |
| Chronic Fatigue Panel | 9 tests | $169.99 |
Quest vs. Labcorp for Vitamin B12: which lab should you pick?
Both are CLIA-certified national labs and the result is clinically equivalent, so pick whichever location is closer. Your report will print that lab's own reference range, which can differ slightly from the table above.
| Lab | Available | Price |
|---|---|---|
| Quest Diagnostics | Yes | $25.99 |
| Labcorp | Yes | $26.99 |
| BioReference (NY & NJ) | Yes | $24.99 |
Need help choosing a location? Use the lab finder to see draw sites near your ZIP.
Related Vitamins & Nutrients biomarkers
Markers commonly tested alongside Vitamin B12.
Frequently asked
Common in vegetarians/vegans, older adults, and people on metformin or acid-suppressing medications. Can cause anemia and neurological symptoms. A single result below the reference range is a prompt to look closer with a clinician — often a repeat test and related markers — not a diagnosis on its own.
Ready to test your vitamin b12?
Order in two minutes, get physician-approved, and visit a lab the same day. Starts at $25.99.