Acute appendicitis (K35) ICD-10-CM
The K35 code range covers acute appendicitis with 20 ICD-10-CM diagnosis codes. 13 of them are billable and valid for claim submission in fiscal year 2027, and the category headers group them but cannot themselves be billed.
Codes in the K35 Range 20 codes · 13 billable
- K35 Acute appendicitisNon-billable
- K35.2 Acute appendicitis with generalized peritonitisNon-billable
- K35.20 Acute appendicitis with generalized peritonitis, without abscessNon-billable
- K35.200 Acute appendicitis with generalized peritonitis, without perforation or abscess
- K35.201 Acute appendicitis with generalized peritonitis, with perforation, without abscess
- K35.209 Acute appendicitis with generalized peritonitis, without abscess, unspecified as to perforation
- K35.21 Acute appendicitis with generalized peritonitis, with abscessNon-billable
- K35.210 Acute appendicitis with generalized peritonitis, without perforation, with abscess
- K35.211 Acute appendicitis with generalized peritonitis, with perforation and abscess
- K35.219 Acute appendicitis with generalized peritonitis, with abscess, unspecified as to perforation
- K35.3 Acute appendicitis with localized peritonitisNon-billable
- K35.30 Acute appendicitis with localized peritonitis, without perforation or gangrene
- K35.31 Acute appendicitis with localized peritonitis and gangrene, without perforation
- K35.32 Acute appendicitis with perforation, localized peritonitis, and gangrene, without abscess
- K35.33 Acute appendicitis with perforation, localized peritonitis, and gangrene, with abscess
- K35.8 Other and unspecified acute appendicitisNon-billable
- K35.80 Unspecified acute appendicitis
- K35.89 Other acute appendicitisNon-billable
- K35.890 Other acute appendicitis without perforation or gangrene
- K35.891 Other acute appendicitis without perforation, with gangrene
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the K35 range.
Appendicitis
Acute inflammation of the vermiform appendix.
About the K35 Code Range
Appendicitis is inflammation of the appendix; here, the condition is acute. These codes distinguish generalized or localized peritonitis from other or unspecified acute appendicitis.
K35.2 identifies generalized peritonitis. Its subdivisions distinguish whether an abscess is present and whether perforation is present, absent, or unspecified. K35.3 identifies localized peritonitis, with further distinctions for perforation, gangrene, and abscess. K35.8 contains other and unspecified acute appendicitis. Its other-appendicitis subdivisions distinguish whether gangrene is present when there is no perforation.
Questions About This Page
How many billable codes are in the K35 range?
Of the 20 codes in this range, 13 are billable and valid for claim submission from October 1, 2026 through September 30, 2027. Category header codes group them but cannot be reported on claims.
What does the K35 range classify?
The range classifies acute appendicitis. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2027 ICD-10-CM Tabular List and order file, effective October 1, 2026 through September 30, 2027.
