Lab tests CPT 84681 Illinois Outpatient

C-peptide test cost in Illinois

In Illinois, 100 hospitals publish a cash price for C-peptide blood test: from $9.32 to $539.06, with a median of $103.60. The lowest price is at Riverside Medical Center (Kankakee). The highest price is 57.8× the lowest.

Outpatient cash prices, one line per hospital — its lowest listed price for code 84681. Prices for both sides of the body and inpatient prices are not mixed in. Collected Sep 29, 2026. See them on a map

Lowest$9.32Riverside Medical Center

Median$103.60half pay less

Highest$539.06in Illinois

Lowest saves$94.28vs the median

Hospitals in Illinois, cheapest first

Hospital	Cash price	List price	File date
Riverside Medical Center lowest Kankakee · Kankakee, IL ASSAY OF C-PEPTIDE	$9.32	$35.00	— source file
Roseland Community Hospital Chicago · Chicago-Naperville-Elgin, IL-IN C-peptide (protein) level	$12.17	$52.03	Jul 1, 2026 source file
The Carle Foundation Hospital Urbana · Champaign-Urbana, IL C-Peptide, S Ref	$13.00	$13.00	Apr 15, 2026 source file
Uchicago Medicine AdventHealth Bolingbrook Bolingbrook · Chicago-Naperville-Elgin, IL-IN HC C PEPTIDE LEVEL - ARUP	$18.25	$73.00	Apr 1, 2026 source file
Uchicago Medicine AdventHealth Glenoaks Glendale Heights · Chicago-Naperville-Elgin, IL-IN HC ASSAY OF C-PEPTIDE - C-PEPTIDE	$18.25	$73.00	Apr 1, 2026 source file
Uchicago Medicine AdventHealth Hinsdale Hinsdale · Chicago-Naperville-Elgin, IL-IN HC ASSAY OF C-PEPTIDE - C-PEPTIDE	$18.25	$73.00	Apr 1, 2026 source file
Uchicago Medicine AdventHealth La Grange La Grange · Chicago-Naperville-Elgin, IL-IN HC ASSAY OF C-PEPTIDE - C-PEPTIDE	$18.25	$73.00	Apr 1, 2026 source file
Mercy Medical Center Aurora · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$20.00	$470.00	Sep 1, 2026 source file
Saint Francis Hospital Evanston · Chicago-Naperville-Elgin, IL-IN HC ASSAY OF C-PEPTIDE	$20.00	$94.00	Sep 1, 2026 source file
Saint Joseph Medical Center - Joliet Joliet · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$20.00	$478.00	Sep 1, 2026 source file
Gottlieb Memorial Hospital Melrose Park · Chicago-Naperville-Elgin, IL-IN C-Peptide (Wcpe)	$24.32	$128.00	Mar 31, 2026 source file
MacNeal Hospital Berwyn · Chicago-Naperville-Elgin, IL-IN C-Peptide (Wcpe)	$24.32	$128.00	Mar 31, 2026 source file
Louis A Weiss Memorial Hospital Chicago · Chicago-Naperville-Elgin, IL-IN C-Peptide, Serum SO	$29.14	$85.71	Mar 17, 2025 source file
Loyola University Medical Center Maywood · Chicago-Naperville-Elgin, IL-IN C-Peptide (Wcpe)	$29.44	$128.00	Mar 31, 2026 source file
FHN Memorial Hospital Freeport · Freeport, IL C-peptide (protein) level	$30.45	$38.06	Jan 22, 2026 source file
Presence Saint Joseph Hospital - Chicago Chicago · Chicago-Naperville-Elgin, IL-IN HC C-PEPTIDE, SERUM	$31.02	$94.00	— source file
John H. Stroger, Jr. Hospital Chicago · Chicago-Naperville-Elgin, IL-IN RL-C-PEPTIDE	$37.10	$53.00	— source file
Humboldt Park Health Chicago · Chicago-Naperville-Elgin, IL-IN C-peptide (protein) level	$52.63	$187.95	Aug 24, 2026 source file
MercyOne Genesis Aledo Medical Center Aledo · Davenport-Moline-Rock Island, IA-IL GHS C-PEPTIDE	$59.40	$99.00	Mar 31, 2026 source file
Ferrell Hospital Community Foundation Eldorado · Eldorado, IL HC C PEPTIDE	$60.00	$80.00	Sep 22, 2026 source file
Carle BroMenn Medical Center Normal · Bloomington, IL C-Peptide, S Ref	$62.00	$62.00	Apr 15, 2026 source file
Carlinville Area Hospital Carlinville · St. Louis, MO-IL C-PEPTID	$63.00	$90.00	— source file
Richland Memorial Hospital Olney · Olney, IL ARUP Serum, C-Peptide	$63.00	$63.00	Apr 15, 2026 source file
Trinity Rock Island Rock Island · Davenport-Moline-Rock Island, IA-IL HC C-PEPTIDE	$64.28	$80.35	Jan 28, 2026 source file
Hoopeston Community Memorial Hospital Hoopeston · Danville, IL ARUP Serum, C-Peptide	$66.00	$66.00	Apr 15, 2026 source file
Community First Medical Center Chicago · Chicago-Naperville-Elgin, IL-IN C-peptide (protein) level	$72.25	$144.50	Apr 1, 2026 source file
Morris Hospital Morris · Chicago-Naperville-Elgin, IL-IN C-peptide (protein) level	$74.83	$311.00	Jun 30, 2026 source file
Hopedale Medical Complex Hopedale · Peoria, IL C-PEPTIDE	$75.50	$107.86	— source file
MercyOne Genesis Silvis Medical Center Silvis · Davenport-Moline-Rock Island, IA-IL #CPeptide	$78.60	$131.00	Mar 31, 2026 source file
Carle Eureka Hospital Eureka · Peoria, IL C-Peptide, S Ref	$83.00	$83.00	Apr 15, 2026 source file
Advocate Childrens Hospital Oak Lawn Oak Lawn · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$100.00	$200.00	Nov 4, 2025 source file
Advocate Childrens Hospital Park Ridge Park Ridge · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$100.00	$200.00	Nov 4, 2025 source file
Advocate Christ Medical Center Oak Lawn · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$100.00	$200.00	Nov 4, 2025 source file
Advocate Condell Medical Center Libertyville · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$100.00	$200.00	Nov 4, 2025 source file
Advocate Good Samaritan Hospital Downers Grove · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$100.00	$200.00	Nov 4, 2025 source file
Advocate Good Shepherd Hospital Barrington · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$100.00	$200.00	Nov 4, 2025 source file
Advocate Illinois Masonic Medical Center Chicago · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$100.00	$200.00	Nov 4, 2025 source file
Advocate Lutheran General Hospital Park Ridge · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$100.00	$200.00	Nov 4, 2025 source file
Advocate Sherman Hospital Elgin · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$100.00	$200.00	Nov 4, 2025 source file
Advocate South Suburban Hospital Hazel Crest · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$100.00	$200.00	Nov 4, 2025 source file
Advocate Trinity Hospital Chicago · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$100.00	$200.00	Nov 4, 2025 source file
Community Hospital of Staunton Staunton · St. Louis, MO-IL C PEPTIDE	$103.45	$206.90	Feb 9, 2026 source file
Northwestern Lake Forest Hospital Lake Forest · Chicago-Naperville-Elgin, IL-IN HB Ref Cardio Iq Insulin Resistance Panel W/Score, C-Peptide (Q)	$103.60	$148.00	Apr 1, 2026 source file
Northwestern Medicine Central DuPage Hospital Winfield · Chicago-Naperville-Elgin, IL-IN HB Ref Cardio Iq Insulin Resistance Panel W/Score, C-Peptide (Q)	$103.60	$148.00	Apr 1, 2026 source file
Northwestern Medicine Delnor Hospital Geneva · Chicago-Naperville-Elgin, IL-IN HB Ref Cardio Iq Insulin Resistance Panel W/Score, C-Peptide (Q)	$103.60	$148.00	Apr 1, 2026 source file
Northwestern Medicine Kishwaukee Hospital DeKalb · Chicago-Naperville-Elgin, IL-IN HB Ref Cardio Iq Insulin Resistance Panel W/Score, C-Peptide (Q)	$103.60	$148.00	Apr 1, 2026 source file
Northwestern Medicine Marianjoy Rehabilitation Hospital Wheaton · Chicago-Naperville-Elgin, IL-IN HB Ref Cardio Iq Insulin Resistance Panel W/Score, C-Peptide (Q)	$103.60	$148.00	Apr 1, 2026 source file
Northwestern Medicine McHenry Hospital McHenry · Chicago-Naperville-Elgin, IL-IN HB Ref Cardio Iq Insulin Resistance Panel W/Score, C-Peptide (Q)	$103.60	$148.00	Apr 1, 2026 source file
Northwestern Medicine Valley West Hospital Sandwich · Chicago-Naperville-Elgin, IL-IN HB Ref Cardio Iq Insulin Resistance Panel W/Score, C-Peptide (Q)	$103.60	$148.00	Apr 1, 2026 source file
Northwestern Memorial Hospital Chicago · Chicago-Naperville-Elgin, IL-IN HB Ref Cardio Iq Insulin Resistance Panel W/Score, C-Peptide (Q)	$103.60	$148.00	Apr 1, 2026 source file
Palos Community Hospital Palos Heights · Chicago-Naperville-Elgin, IL-IN HB Ref Cardio Iq Insulin Resistance Panel W/Score, C-Peptide (Q)	$103.60	$148.00	Apr 1, 2026 source file
Resilience Healthcare West Suburban Medical Center Oak Park · Chicago-Naperville-Elgin, IL-IN C-Peptide, Serum SO	$110.27	$324.32	Mar 17, 2025 source file
Touchette Regional Hospital Cahokia Heights · St. Louis, MO-IL C-peptide	$113.46	$183.00	— source file
Crawford Memorial Hospital Robinson · Robinson, IL C-Peptide LC	$116.80	$146.00	— source file
NorthShore University HealthSystems Glenbrook Hospital Glenview · Chicago-Naperville-Elgin, IL-IN R C-Peptide Urine	$118.95	$183.00	— source file
NorthShore University HealthSystems Skokie Hospital Skokie · Chicago-Naperville-Elgin, IL-IN R C-Peptide Urine	$118.95	$183.00	— source file
Deaconess Illinois Crossroads Mount Vernon · Mount Vernon, IL HC C-PEPTIDE REF	$121.14	$550.61	Feb 3, 2026 source file
Sarah Bush Lincoln Health Center Mattoon · Charleston-Mattoon, IL C-peptide (protein) level	$130.00	$130.00	Jun 3, 2026 source file
Hshs Holy Family Hospital Greenville · St. Louis, MO-IL HC C PEPTIDE-90	$130.32	$181.00	— source file
Anderson Hospital Maryville · St. Louis, MO-IL C PEPTIDE	$133.40	$266.80	Feb 6, 2026 source file
La Rabida Children's Hospital Chicago · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$134.50	$134.50	Apr 1, 2026 source file
Thomas H Boyd Memorial Hospital Carrollton · Carrollton, IL C-peptide (protein) level	$142.40	$178.00	Jul 7, 2026 source file
Heartland Regional Medical Center Marion · Marion-Herrin, IL HC C-PEPTIDE REF	$143.11	$753.17	Feb 3, 2026 source file
Shriners Childrens - Chicago Chicago · Chicago-Naperville-Elgin, IL-IN ASSAY OF C-PEPTIDE	$149.20	$149.20	— source file
Rochelle Community Hospital Rochelle · Rochelle, IL C-peptide (protein) level	$162.00	$162.00	Aug 6, 2026 source file
Illini Community Hospital Pittsfield · Pittsfield, IL HC ASSAY OF C-PEPTIDE - C-PEPTIDE	$180.17	$300.28	Jun 8, 2026 source file
Endeavor Health Highland Park Hospital Highland Park · Chicago-Naperville-Elgin, IL-IN HB R C-PEPTIDE,URINE	$183.00	$183.00	Apr 1, 2026 source file
Northshore University Healthsystem - Evanston Hospital Evanston · Chicago-Naperville-Elgin, IL-IN HB R C-PEPTIDE,URINE	$183.00	$183.00	Apr 1, 2026 source file
Swedish Covenant Health Chicago · Chicago-Naperville-Elgin, IL-IN HB R C-PEPTIDE,URINE	$183.00	$183.00	Apr 1, 2026 source file
Fayette County Hospital Vandalia · Vandalia, IL C-peptide (protein) level	$184.00	$184.00	Jun 12, 2026 source file
Sarah D Culbertson Memorial Hospital Rushville · Rushville, IL C-peptide (protein) level	$189.90	$211.00	May 26, 2026 source file
Blessing Hospital Quincy · Quincy, IL-MO HC ASSAY OF C-PEPTIDE - C-PEPTIDE	$198.87	$331.45	Jun 8, 2026 source file
Northwest Community Hospital Arlington Heights · Chicago-Naperville-Elgin, IL-IN Hb Assay Of C-Peptide	$202.00	$202.00	Apr 1, 2026 source file
Carle Health Pekin Hospital Pekin · Peoria, IL C-Peptide	$210.00	$210.00	Apr 15, 2026 source file
Methodist Medical Center of Illinois Peoria · Peoria, IL C-Peptide	$210.00	$210.00	Apr 15, 2026 source file
Proctor Community Hospital Peoria · Peoria, IL C-Peptide	$210.00	$210.00	Apr 15, 2026 source file
Morrison Community Hospital Morrison · Sterling, IL C-PEPTIDE	$214.00	$214.00	— source file
Sparta Community Hospital Sparta · Sparta, IL C PEPTIDE	$223.00	$223.00	— source file
Pana Community Hospital Pana · Taylorville, IL C-Peptide, Serum LC	$223.25	$223.25	— source file
County of Clay Flora · Flora, IL LCHG C-PEPTIDE	$231.00	$231.00	May 7, 2026 source file
Mercyhealth Hospital & Medical Center - Harvard Harvard · Chicago-Naperville-Elgin, IL-IN CHG ASSAY OF C-PEPTIDE	$232.46	$309.94	Mar 1, 2026 source file
Mercyhealth Crystal Lake Hospital & Medical Center Crystal Lake · Chicago-Naperville-Elgin, IL-IN CHG ASSAY OF C-PEPTIDE	$237.32	$316.42	Mar 1, 2026 source file
Fairfield Memorial Hospital Fairfield · Fairfield, IL C-PEPTIDE	$242.40	$303.00	— source file
Ingalls Memorial Hospital Harvey · Chicago-Naperville-Elgin, IL-IN Hc C-Peptide	$246.00	$246.00	Apr 1, 2026 source file
Pinckneyville Community Hospital Pinckneyville · Pinckneyville, IL C-peptide (protein) level	$254.00	$254.00	Jun 8, 2026 source file
Hammond Henry Dist Hospital Geneseo · Davenport-Moline-Rock Island, IA-IL C-peptide (protein) level	$257.40	$286.00	Jan 22, 2026 source file
Rockford Memorial Hospital Rockford · Rockford, IL CHG ASSAY OF C-PEPTIDE	$285.65	$380.87	Mar 1, 2026 source file
Edward Hospital Naperville · Chicago-Naperville-Elgin, IL-IN HC C - PEPTIDE	$298.00	$298.00	Apr 1, 2026 source file
Elmhurst Memorial Hospital Elmhurst · Chicago-Naperville-Elgin, IL-IN HC C - PEPTIDE	$298.00	$298.00	Apr 1, 2026 source file
City of Clinton Clinton · Clinton, IL C-peptide (protein) level	$298.55	$298.55	Jun 8, 2026 source file
Washington County Hospital Nashville · Nashville, IL LCHG C-PEPTIDE	$304.80	$381.00	Jun 1, 2026 source file
Vista Medical Center East Waukegan · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$362.92	$362.92	— source file
Gibson Community Hospital Gibson City · Champaign-Urbana, IL C-PEPTIDE	$376.00	$376.00	— source file
The University of Chicago Medical Center Chicago · Chicago-Naperville-Elgin, IL-IN Hc C-Peptide	$404.00	$404.00	Apr 1, 2026 source file
Harrisburg Medical Center Harrisburg · Harrisburg, IL HC C-Peptide	$408.80	$511.00	Mar 4, 2026 source file
Herrin Hospital Herrin · Marion-Herrin, IL HC C-Peptide	$408.80	$511.00	Mar 4, 2026 source file
Memorial Hospital of Carbondale Carbondale · Carbondale, IL HC C-Peptide	$408.80	$511.00	Mar 4, 2026 source file
St Joseph Memorial Hospital Murphysboro · Carbondale, IL HC C-Peptide	$408.80	$511.00	Mar 4, 2026 source file
Jackson Park Hospital Foundation Chicago · Chicago-Naperville-Elgin, IL-IN C-PEPTIDE	$489.90	$612.37	— source file
Gateway Regional Medical Center Granite City · St. Louis, MO-IL C-PEPTIDE	$539.06	$898.44	— source file

By metro area

Each metro page compares every listing, including prices for both sides of the body.

Metro area	Hospitals	Lowest	Median
Chicago-Naperville-Elgin, IL-IN	54	$12.17	$100.00
St. Louis, MO-IL	6	$63.00	$121.89
Peoria, IL	5	$75.50	$210.00
Davenport-Moline-Rock Island, IA-IL	4	$59.40	$71.44
Carbondale, IL	2	$408.80	$408.80
Champaign-Urbana, IL	2	$13.00	$194.50
Marion-Herrin, IL	2	$143.11	$275.96
Bloomington, IL	1	$62.00	$62.00
Carrollton, IL	1	$142.40	$142.40
Clinton, IL	1	$298.55	$298.55
Charleston-Mattoon, IL	1	$130.00	$130.00
Danville, IL	1	$66.00	$66.00
Eldorado, IL	1	$60.00	$60.00
Fairfield, IL	1	$242.40	$242.40
Flora, IL	1	$231.00	$231.00
Freeport, IL	1	$30.45	$30.45
Harrisburg, IL	1	$408.80	$408.80
Kankakee, IL	1	$9.32	$9.32
Mount Vernon, IL	1	$121.14	$121.14
Nashville, IL	1	$304.80	$304.80
Olney, IL	1	$63.00	$63.00
Pinckneyville, IL	1	$254.00	$254.00
Pittsfield, IL	1	$180.17	$180.17
Quincy, IL-MO	1	$198.87	$198.87
Robinson, IL	1	$116.80	$116.80
Rushville, IL	1	$189.90	$189.90
Rochelle, IL	1	$162.00	$162.00
Rockford, IL	1	$285.65	$285.65
Sparta, IL	1	$223.00	$223.00
Sterling, IL	1	$214.00	$214.00
Taylorville, IL	1	$223.25	$223.25
Vandalia, IL	1	$184.00	$184.00

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.

C-peptide blood test in other states

Median cash price across the state's hospitals.