The short answer
Measures insulin production from the pancreas — distinguishes between Type 1 and Type 2 diabetes, measured from a standard blood draw. At TestWell it costs $29.99 plus a $6 lab fee, requires an 8–12 hour fast, and results post in 2–4 business days. Physician-authorized with no doctor's visit or insurance needed; draw at Labcorp.
Hospital Lab
$150
cash pay
Other Labs
$35
+ lab fees
TestWell
$29.99
+ $6 lab fee
C-Peptide is a byproduct of insulin production released by the pancreas in equal amounts to insulin. Unlike insulin itself, C-Peptide is not affected by external insulin injections, making it the gold standard for measuring how much insulin your body is naturally producing. It is essential for differentiating Type 1 diabetes (low C-Peptide) from Type 2 (normal or high C-Peptide), and for assessing pancreatic beta cell function over time.
Diabetes and blood-sugar testing identifies insulin resistance, pre-diabetes, and diabetes early — when lifestyle changes still have the highest impact.
Adults with risk factors for diabetes: family history, overweight/obesity, sedentary lifestyle, prior gestational diabetes, or signs like increased thirst, fatigue, or unexplained weight changes.
Sample Type
Blood draw
Fasting
Required
Results In
2–4 business days
Performed At
Labcorp
Your C-Peptide 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.
Fasting for 8–12 hours required.
A C-Peptide test costs $29.99 at TestWell — $35.99 all-in when ordered alone, because the $6 lab processing fee is charged once per order, with no draw fee or physician fee added. Hospital outpatient labs typically bill around $150.00 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.
| Where you order | Price | One test, all-in | Notes |
|---|---|---|---|
| TestWell (drawn at Quest or Labcorp) | $29.99 | $35.99 | Includes the one $6 lab processing fee, charged once per order |
| Hospital outpatient lab, self-pay (typical) | $150.00 | $150.00 | Reference figure; hospital charges vary widely by facility and are often higher |
Lab test codes: Quest test code 90896 · Labcorp test no. 010108. Competitor prices are read from the linked public pages and re-checked regularly; the labs' sites may add taxes or change prices without notice.
TestWell Price
$29.99
+ $6 lab processing fee at checkout
No insurance needed · HIPAA compliant
Better value: the Pre-Diabetes Panel
Save $34.96This test is part of the Pre-Diabetes Panel — 5 tests · 8 biomarkers for $89.99, $34.96 less than à la carte.
$89.99$124.95
5 tests · 8 biomarkers
Frequently ordered together
Customers who ordered C-Peptide also added these for a more complete health picture.
Not sure where to start?
C-Peptide
$29.99