ICD-10-CM 2027
ICD-10 code for rectosigmoid ulcer
From the official ICD-10-CM alphabetic index entry “Ulcer, ulcerated, ulcerating, ulceration, ulcerative › rectosigmoid”. Page updated September 29, 2026.
About coding rectosigmoid ulcer
The ICD-10-CM code for rectosigmoid ulcer is K63.3 (Ulcer of intestine). The official index lists 1 more specific code, so check the documentation for details such as type, cause, site or severity before settling on K63.3.
Within K63 (other diseases of intestine), K63.3 is specifically for ulcer of intestine. Related codes cover abscess of intestine (K63.0), perforation of intestine (nontraumatic) (K63.1), fistula of intestine (K63.2), Enteroptosis (K63.4), polyp of colon (K63.5), other specified diseases of intestine (K63.8) and disease of intestine, unspecified (K63.9).
Don't report K63.3 together with the conditions in its Excludes1 note: duodenal ulcer (K26.-), gastrointestinal ulcer (K28.-), gastrojejunal ulcer (K28.-), jejunal ulcer (K28.-) and 4 more.
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
More specific rectosigmoid ulcer codes (official index)
- with perforation K63.1 — Perforation of intestine (nontraumatic)
Don't confuse with (Excludes1 for K63.3)
Common questions about rectosigmoid ulcer ICD-10 codes
What is the ICD-10 code for rectosigmoid ulcer?
- K63.3 — Ulcer of intestine. More specific codes apply when the documentation supports them: K63.1.
Is K63.3 billable?
- Yes. K63.3 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can K63.3 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict K63.3 as a principal diagnosis.
Is K63.3 a CC or MCC?
- K63.3 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.