2026 ICD-10-CM Diagnosis Code K56.3Gallstone ileus

ICD-10-CM Codes›K00–K95›K55-K64›K56

ICD-10-CM K56.3
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

K56.3 is a billable ICD-10-CM diagnosis code for gallstone ileus. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 388 through 390. Coders also document this condition as enterolith. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Biliary tract disease and Intestinal obstruction and ileus.

Code Identity

ICD-10-CM Code
K56.3
Billable Status
Yes — Valid for Submission
Code Describes
Gallstone ileus
Short Description
Gallstone ileus
Same as the full description in the CMS dataset.
Parent Code
K56
Paralytic ileus and intestinal obstruction without hernia

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK55-K64Other diseases of intestines
CategoryK56Paralytic ileus and intestinal obstruction without hernia
This CodeK56.3Gallstone ileus

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Enterolith
  • Enterolith of large intestine
  • Enterolith of small intestine
  • Gallstone ileus
  • Gallstone ileus of large intestine
  • Gallstone ileus of small intestine

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Obstruction of intestine by gallstone

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Gallstone(colic) (cystic duct) (gallbladder) (impacted) (multiple)
      • causing intestinal obstruction
    • Ileus(bowel) (colon) (inhibitory) (intestine)
      • due to gallstone (in intestine)
    • Ileus(bowel) (colon) (inhibitory) (intestine)
      • gallstone
    • Impaction, impacted
      • bowel, colon, rectum
        • by gallstone
    • Impaction, impacted
      • gallstone (s)
        • in intestine, with obstruction (any part)
    • Impaction, impacted
      • intestine (calculous) NEC
        • gallstone, with ileus
    • Obstruction, obstructed, obstructive
      • intestine
        • by gallstone

Clinical ClassificationClinical

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

CCSR DIG017
Biliary tract disease
Default principal diagnosis: inpatient No · outpatient No
CCSR DIG012
Intestinal obstruction and ileus
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Gallstones

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 K56.3 to ICD-9-CMHistory

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

ICD-9-CM
560.31 Gallstone ileus
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 K56.3Overview

Is K56.3 (Paralytic ileus and intestinal obstruction without hernia) a billable code?

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

What MS-DRG does K56.3 group to?

When gallstone ileus is the principal diagnosis on an inpatient stay, it groups to MS-DRG 388, 389, 390, with relative weights from 0.5440 to 1.4768 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of K56.3?

Under the General Equivalence Mappings, gallstone ileus converts to ICD-9-CM 560.31 (gallstone ileus). The mapping is a direct match.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.