K56.3 Gallstone ileus

The ICD-10-CM code for Gallstone ileus is K56.3 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

11: Diseases of the digestive system (K00-K95)

Section

K55-K64: Other diseases of intestines (K55-K64)

Category K56

22 codes (16 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to K56.3:

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

Inclusion Terms

• Obstruction of intestine by gallstone

U.S. Hospital Utilization

• An estimated 1,555 U.S. inpatient stays in 2023 included K56.3 among the documented diagnoses.
• 860 stays listed it as the principal diagnosis.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Official Coding Guidelines

Chapter 11 reserved for future expansion

11. Chapter 11: Diseases of the Digestive System (K00-K95) Reserved for future guideline expansion

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool
• AHRQ — HCUP National Inpatient Sample, Frequencies by Diagnosis Code (2016–2023)