K35.8Header code — not billable
Other and unspecified acute appendicitis
- Chapter
- 11. Diseases of the digestive system
- Category
- K35
- Effective date
- October 1, 2026
Related codes in category K35
K35Acute appendicitisK35.2Acute appendicitis with generalized peritonitisK35.20Acute appendicitis with gen peritonitis, without abscessK35.200Acute appendicitis with gen peritonitis, w/o perf or abscsYesK35.201Ac appendicitis with gen peritonitis, with perf, w/o abscsYesK35.209Ac appendicitis w gen peritonitis,w/o abscs,unsp as to perfYesK35.21Acute appendicitis with gen peritonitis, with abscessK35.210Ac appendicitis with gen peritonitis, w/o perf, with abscsYesK35.211Acute appendicitis with gen peritonitis, with perf and abscsYesK35.219Ac appendicitis w gen peritonitis, w abscs, unsp as to perfYesK35.3Acute appendicitis with localized peritonitisK35.30Acute appendicitis with loc peritonitis, w/o perf or gangrYes
Frequently asked questions
What is ICD-10 code K35.8?
K35.8 is an ICD-10-CM diagnosis code for Other and unspecified acute appendicitis.
Is K35.8 a billable code?
No. K35.8 is a category/header code, not billable on its own — use one of its more specific child codes instead.
What ICD-10-CM chapter is K35.8 in?
K35.8 falls under Chapter 11: Diseases of the digestive system.
When did K35.8 become effective?
K35.8 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.
What other codes are related to K35.8?
K35.8 belongs to category K35, which includes 12 other codes — see the related codes list on this page.
ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.