2026 ICD-10-CM Diagnosis Code C23Malignant neoplasm of gallbladder

ICD-10-CM Codes›C00–D49›C15-C26›C23

ICD-10-CM C23
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

C23 is a billable ICD-10-CM diagnosis code for malignant neoplasm of gallbladder. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 435 through 437. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Gastrointestinal cancers - gallbladder.

Code Identity

ICD-10-CM Code
C23
Billable Status
Yes — Valid for Submission
Code Describes
Malignant neoplasm of gallbladder
Short Description
Malignant neoplasm of gallbladder
Same as the full description in the CMS dataset.
Chapter
C15-C26
Malignant neoplasms of digestive organs

Code Classification

ChapterC00–D49Neoplasms
SectionC15-C26Malignant neoplasms of digestive organs
CategoryC23Malignant neoplasm of gallbladder
This CodeC23Malignant neoplasm of gallbladder

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Carcinoma of gallbladder
  • Local recurrence of malignant neoplasm of gallbladder
  • Malignant mesenchymal neoplasm of gallbladder
  • Malignant neoplasm of gallbladder
  • Primary adenocarcinoma of gallbladder
  • Primary carcinoma liver and/or biliary system
  • Primary carcinoma of gallbladder
  • Primary malignant mesenchymal neoplasm of gallbladder
  • Primary malignant neoplasm of gallbladder
  • Primary squamous cell carcinoma of gallbladder and extrahepatic biliary tract
  • Squamous cell carcinoma of gallbladder and extrahepatic biliary tract

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NEO019
Gastrointestinal cancers - gallbladder
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Acalculous Cholecystitis

    inflammation of the gallbladder wall in the absence of gallstones.

  • Biliary Dyskinesia

    a motility disorder characterized by biliary colic, absence of gallstones, and an abnormal gallbladder ejection fraction. it is caused by gallbladder dyskinesia and/or sphincter of oddi dysfunction.

  • Cholecystitis

    inflammation of the gallbladder; generally caused by impairment of bile flow, gallstones in the biliary tract, infections, or other diseases.

  • Gallbladder

    a storage reservoir for bile secretion. gallbladder allows the delivery of bile acids at a high concentration and in a controlled manner, via the cystic duct to the duodenum, for degradation of dietary lipid.

  • Gallbladder Diseases

    diseases of the gallbladder. they generally involve the impairment of bile flow, gallstones in the biliary tract, infections, neoplasms, or other diseases.

  • Gallbladder Emptying

    a process whereby bile is delivered from the gallbladder into the duodenum. the emptying is caused by both contraction of the gallbladder and relaxation of the sphincter mechanism at the choledochal terminus.

  • Gallbladder Neoplasms

    tumors or cancer of the gallbladder.

Table of NeoplasmsClinical

Anatomical sites in the Table of Neoplasms that reference this code family.

SiteMalig.
Primary		Malig.
Secondary		Ca
in situ		BenignUncertainUnspec.
gallbladderC23C78.89D01.5D13.5D37.6D49.0

Patient EducationClinical

Gallbladder Cancer

Your gallbladder is a pear-shaped organ under your liver. It stores bile, a fluid made by your liver to digest fat. As your stomach and intestines digest food, your gallbladder releases bile through a tube called the common bile duct. The duct connects your gallbladder and liver to your small intestine.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert C23 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
156.0 Malig neo gallbladder
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About C23Overview

Is C23 (Malignant neoplasm of gallbladder) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report malignant neoplasm of gallbladder on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does C23 group to?

When malignant neoplasm of gallbladder is the principal diagnosis on an inpatient stay, it groups to MS-DRG 435, 436, 437, with relative weights from 0.8533 to 1.8367 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of C23?

Under the General Equivalence Mappings, malignant neoplasm of gallbladder converts to ICD-9-CM 156.0 (malig neo gallbladder). The mapping is a direct match.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.