Also known as: B12 Test, Cobalamin
On your lab requisition: Quest “Vitamin B12 (Cobalamin)” (test code 927)
The short answer
Essential for nerve function, energy production, and red blood cell formation, measured from a standard blood draw. At TestWell it costs $25.99 plus a $6 lab processing fee, needs no fasting, and results post in 2–4 business days. Physician-authorized with no doctor's visit or insurance needed; draw at Quest or Labcorp.
Hospital Lab
$100
cash pay
Other Labs
$49
+ lab fees
TestWell
$25.99
+ $6 lab processing fee
Vitamin B12 is crucial for nerve function, DNA synthesis, red blood cell production, and brain health. Deficiency can cause fatigue, weakness, numbness and tingling, memory problems, and anemia. It's especially common in vegans/vegetarians, older adults, and those taking certain medications like metformin or proton pump inhibitors.
Essential for nerve function and red blood cell production. Deficiency causes fatigue, neuropathy, megaloblastic anemia, and (if prolonged) irreversible neurologic damage.
Vegans/vegetarians, anyone over 50, people on metformin or PPIs (both deplete B12), patients with unexplained fatigue, brain fog, tingling/numbness, or balance issues.
Sample Type
Blood draw
Fasting
Not required
Results In
2–4 business days
Performed At
Quest or Labcorp
Your Vitamin B12 results will include values for each of the 1 biomarker tested, along with reference ranges. Results are reviewed by a licensed physician before being released to your secure portal.
If any values fall outside the normal range, your report will include guidance on what that may mean and recommended next steps. You'll receive an email notification when your results are ready, typically within 2–4 business days.
Typical reference range layout
Lab reports show where your value sits relative to established reference intervals—your physician interprets this in context for you. Already have results? Analyze them with your AI assistant against our physician-reviewed ranges.
No fasting required. Biotin supplements may interfere — stop 72 hours before.
What can throw off this result
Physician-reviewed “Before your test” pages — what each factor does, for how long, and what to do about it.
The short answer
Worth it if you have fatigue, nerve symptoms, or a reason to be low - and genuinely valuable for vegans, older adults, and anyone on metformin or long-term acid reducers. At $25.99 it is a cheap, high-yield test; a B12 deficiency is very treatable once you know it is there.
We would rather you order the right test than the most expensive one.
Vitamin B12 is a simple venous draw at Quest or Labcorp, or an at-home mobile draw where available - no fasting required. One prep note that trips people up: high-dose biotin supplements can interfere with the assay, so stop biotin for 72 hours before your draw. If B12 is borderline, pairing it with methylmalonic acid (MMA) or [folate](/tests/folate) confirms a true tissue deficiency.
The markers that matter most and what an out-of-range value can mean. Reference ranges vary by lab, age and sex.
| Marker | Typical range | What it means |
|---|---|---|
| Vitamin B12 (serum) | ~200-900 pg/mL | Under ~200 pg/mL indicates deficiency; 200-300 is borderline and often confirmed with an MMA test; high levels are usually just supplementation and rarely a concern on their own. |
This section medically reviewed by Youmna DiStefano, MD — updated July 2026. General health information, not medical advice; interpret results with a qualified clinician.
A Vitamin B12 test costs $25.99 at TestWell — $31.99 all-in when ordered alone, because the $6 lab processing fee is charged once per order, with no draw fee or physician fee added. Ordered directly from the labs' own consumer sites, the same test lists at $49.00 at Quest Health and $49.00 at Labcorp OnDemand (list prices checked Sep 12, 2026). Hospital outpatient labs typically bill around $100.00 self-pay for the same test, and often more. With insurance, what you pay depends on your deductible and your plan's negotiated rate; TestWell's price is fixed before the draw and is HSA/FSA-eligible. Full cost breakdown →
| Where you order | Price | One test, all-in | Notes |
|---|---|---|---|
| TestWell (drawn at Quest) | $25.99 | $31.99 | Includes the one $6 lab processing fee, charged once per order |
| TestWell (drawn at Labcorp) | $26.99 | $32.99 | Labcorp's own cost for this test is higher; same order, same portal, same physician review |
| TestWell (drawn at BioReference — New York & New Jersey) | $24.99 | $30.99 | New York and New Jersey orders route to BioReference; Quest Health and Labcorp OnDemand don't take self-ordered draws in those states |
| Quest Health (Quest Diagnostics' own site) | $49.00 | $49.00 | list price checked Sep 12, 2026 |
| Labcorp OnDemand (Labcorp's own site) | $49.00 | $49.00 | list price checked Sep 12, 2026 |
| Hospital outpatient lab, self-pay (typical) | $100.00 | $100.00 | Reference figure; hospital charges vary widely by facility and are often higher |
35% less than the lower lab-direct list price, for the same draw at the same lab. Lab test codes: Quest test code 927 · Labcorp test no. 001503 · BioReference code 0160-2. Competitor prices are read from the linked public pages and re-checked regularly; the labs' sites may add taxes or change prices without notice.
Compare more: Quest Diagnostics price list · Labcorp price list · Quest vs Labcorp · Lab test price checker
Standard ranges start at ~200 pg/mL, but neurologic symptoms can occur at levels under 400. Many functional clinicians target 600-900 pg/mL for optimal nerve function. If your level is in the 200-400 'gray zone' but you have symptoms, add methylmalonic acid (MMA) testing — it confirms functional B12 deficiency even when serum B12 looks OK.
B12 absorption requires stomach acid to release it from food protein (which PPIs suppress) and intrinsic factor for transport across the gut wall (which metformin interferes with). Anyone on long-term PPIs (Prilosec, Nexium, omeprazole) or metformin should test B12 annually.
B12 alone is sufficient if you've already ruled out folate deficiency. The B12 + Folate bundle is better when investigating macrocytic anemia (large red blood cells on a CBC) because both deficiencies look similar on smear.
On TestWell, Vitamin B12 is $25.99. Quest Direct lists the same test at $49, walk-in hospital labs typically bill $80-100 without insurance. Same CLIA-certified labs, same biomarker — TestWell just removes the markup.
The CPT code for serum Vitamin B12 (cobalamin) is 82607. Folate is billed separately as 82746. Methylmalonic acid (functional B12 marker) is 83921.
No fasting required. But hold B12 supplements for at least 24 hours before testing — they can artificially elevate the result and mask a true deficiency.
Annually for vegans/vegetarians, anyone on PPIs or metformin, and adults over 50. Every 3-6 months when correcting a deficiency or after starting B12 injections.
On TestWell a Vitamin B12 test is $25.99 self-pay - no insurance or doctor's visit needed - versus roughly $49 at Quest Direct and $100+ when a hospital bills it uninsured. It is the same B12 assay (CPT 82607) run at Quest or Labcorp, with results in 1-3 business days.
Serum B12 can sit in the low-normal range while your tissues are actually deficient. If symptoms like fatigue or tingling persist, a methylmalonic acid (MMA) test is more sensitive - it rises when B12 is functionally low. Checking ferritin and thyroid is also common in a fatigue work-up, since the causes overlap.
Ordered directly, a Vitamin B12 test lists at $49.00 at Quest Health (Quest Diagnostics' own site) and $49.00 at Labcorp OnDemand (prices checked September 2026). TestWell orders the same test at the same Quest or Labcorp patient service centers for $25.99 — $31.99 all-in with the $6 per-order lab processing fee — paid out of pocket at checkout with no insurance, doctor's visit or draw fee; HSA and FSA cards are accepted.
Vitamin B12 test results are typically ready in 2–4 business days after your draw at Quest or Labcorp. TestWell emails you the moment they post, and your results dashboard shows each marker against its reference range with a plain-English explanation.
Common medications can change a Vitamin B12 test result without anything being wrong. Common medications can lower Vitamin B12 — check B12 periodically on metformin. Each factor is covered on our physician-reviewed "Before your test" pages; when one applies, the fix is usually to remove it and retest.
Order the Vitamin B12 test online from TestWell for $25.99 (plus a $6 per-order lab processing fee) — no doctor's visit, referral or insurance needed. A licensed physician authorizes the order, then you walk into any Quest or Labcorp patient service center near you for the draw (the lab locator on our site lists the closest ones by ZIP code), and results arrive in 2–4 business days.
The Vitamin B12 test is Quest Diagnostics test code 927 ("Vitamin B12 (Cobalamin)"), Labcorp test number 001503, BioReference code 0160-2 (CPT 82607). TestWell orders it under those codes for $25.99 at Quest, Labcorp or BioReference — no doctor's visit or insurance required, results in 2–4 business days. Codes verified against the labs' catalogs in 2026.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
Related guide
Methylmalonic Acid (MMA) and B12 Deficiency: Why the Test Is Ordered and How to Read It
Related guide
CBC With Differential Explained: What Each Value Means and How to Read Your Results
Related guide
Blood Tests After Pregnancy
TestWell Price
$25.99
+ $6 lab processing fee at checkout
No insurance needed · HIPAA compliant
Better value: the Comprehensive B12 Deficiency Panel
Save $23.98This test is part of the Comprehensive B12 Deficiency Panel — 3 tests · 3 biomarkers for $79.99, $23.98 less than à la carte.
$79.99$103.97
3 tests · 3 biomarkers
Frequently ordered together
Customers who ordered Vitamin B12 also added these for a more complete health picture.
Not sure where to start?
Vitamin B12
$25.99