Lab tests CPT 84681 Inpatient — admitted to hospital

C-peptide test cost in San Antonio, TX — inpatient

In San Antonio-New Braunfels, TX, 5 hospitals list a cash price for C-peptide blood test as an inpatient: from $28.50 to $265.20, with a median of $125.28. The lowest listed price is at Guadalupe Regional Medical Center — $96.78 less than the median here. Across Texas, the median is $81.30 at 284 hospitals.

Cash prices at 5 facilities across 3 cities for code 84681, as an inpatient (admitted to hospital) . Collected Sep 29, 2026; the hospital files themselves were last updated between Oct 14, 2025 and Aug 6, 2026.

Lowest$28.50Guadalupe Regional Medical Center
Median$125.28half pay less
Highest$265.20in this market
Difference9.3×highest vs lowest

Where each hospital's price falls

Each dot is one hospital's cash price on a scale from the lowest to the highest in San Antonio-New Braunfels, TX.

median
Lowest $28.50Highest $265.20

Hospitals, cheapest first

HospitalCash price List priceInsurers payOff listFile date
Guadalupe Regional Medical Center lowest Seguin, TX · (830) 379-2411 C-PEPTIDE (PROTEIN) LEVEL $28.50 $57.00 $20.81–$154.20 50% —
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Guadalupe Regional Medical Center lowest Seguin, TX · (830) 379-2411 C-PEPTIDE (PROTEIN) LEVEL $28.50 $57.00 $20.81–$154.20 50% —
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University Health System San Antonio, TX · (210) 358-2000 HC ASSAY OF C-PEPTIDE - C-PEPTIDE $48.00 $192.00 $71.04–$163.20 75% Oct 14, 2025
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Guadalupe Regional Medical Center Seguin, TX · (830) 379-2411 C-PEPTIDE $66.00 $132.00 $20.81–$154.20 50% —
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Guadalupe Regional Medical Center Seguin, TX · (830) 379-2411 C-PEPTIDE $125.00 $250.00 $20.81–$250.00 50% —
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Specialty Hospital of San Antonio Medical Center South San Antonio, TX C-Peptide $125.28 $125.28 $87.70–$112.75 — Aug 6, 2026
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Medina Regional Hospital Hondo, TX · (830) 426-7700 C-PEPTIDE,PLASMA $179.49 $199.43 $99.72–$179.49 10% Jul 29, 2026
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Warm Springs Rehabilitation Hospital of San Antonio San Antonio, TX C-Peptide $265.20 $265.20 $185.64–$238.68 — Aug 6, 2026
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Inpatient: lowest $28.50, median $125.28, highest $265.20 — a 9.3× difference within the same market.

As an outpatient, the same code is billed by 16 facilities here, median $783.04 — that is the price to compare if you are not being admitted.

Cash or insurance?

At 2 of 5 hospitals that publish insurer rates for this code here, the cash price is below the highest rate a health plan has negotiated, and at 1 it is below every plan's rate. If you have insurance but have not met your deductible, you usually pay your plan's negotiated rate, which falls somewhere in the "Insurers pay" column. Paying cash can cost less, but a cash payment usually does not count toward your deductible. Ask the hospital for both numbers before you book.

What it is

A C-peptide test shows how much insulin the pancreas is making. It helps tell type 1 from type 2 diabetes and find the cause of low blood sugar.

What the price covers

The price usually covers running the test. The blood draw (36415) is often billed as a separate line.