ICD-10 Code for Appendicitis
Also indexed as (pneumococcal) (retrocecal)
The ICD-10-CM code for appendicitis is K37 — Unspecified appendicitis. This is the code the Alphabetic Index gives for appendicitis with no further qualifier, valid for FY2027 (October 1, 2026 – September 30, 2027).
BillableUnspecified
K37 is billable but unspecified. If the documentation names a type, site or cause, one of the more specific codes below is likely expected.
Which appendicitis code should you use?
The Alphabetic Index lists 17 codes under Appendicitis. Which one applies depends on the qualifier documented in the record — the type, site, cause, or associated condition. Find the qualifier below, then verify the code in the Tabular List before using it.
By type
| acute | K35.80 | Unspecified acute appendicitis | |
| amebic | A06.89 | Other amebic infections | |
| chronic | K36 | Other appendicitis | |
| healed | K36 | Other appendicitis | |
| interval | K36 | Other appendicitis | |
| neurogenic | K36 | Other appendicitis | |
| obstructive | K36 | Other appendicitis | |
| recurrent | K36 | Other appendicitis | |
| relapsing | K36 | Other appendicitis | |
| ruptured NOS | K35.32 | Acute appendicitis with perforation, localized peritonitis, and gangrene, without abscess | |
| subacute | K36 | Other appendicitis | |
| subsiding | K36 | Other appendicitis | |
| tuberculous | A18.32 | Tuberculous enteritis |
Appendicitis with
| gangrene | K35.891 | Other acute appendicitis without perforation, with gangrene | |
| perforation NOS | K35.32 | Acute appendicitis with perforation, localized peritonitis, and gangrene, without abscess | |
| peritoneal abscess | K35.33 | Acute appendicitis with perforation, localized peritonitis, and gangrene, with abscess | |
| peritonitis NEC | K35.33 | Acute appendicitis with perforation, localized peritonitis, and gangrene, with abscess | |
| gangrene › with localized peritonitis | K35.31 | Acute appendicitis with localized peritonitis and gangrene, without perforation | |
| peritonitis NEC › generalized | K35.209 | Acute appendicitis with generalized peritonitis, without abscess, unspecified as to perforation | |
| peritonitis NEC › localized | K35.30 | Acute appendicitis with localized peritonitis, without perforation or gangrene | |
| peritonitis NEC › rupture | K35.32 | Acute appendicitis with perforation, localized peritonitis, and gangrene, without abscess | |
| peritonitis NEC › generalized › following rupture or perforation of appendix NOS | K35.201 | Acute appendicitis with generalized peritonitis, with perforation, without abscess | |
| peritonitis NEC › generalized › without rupture or perforation of appendix | K35.200 | Acute appendicitis with generalized peritonitis, without perforation or abscess | |
| peritonitis NEC › generalized › with › abscess | K35.219 | Acute appendicitis with generalized peritonitis, with abscess, unspecified as to perforation | |
| peritonitis NEC › generalized › with › perforation or rupture | K35.201 | Acute appendicitis with generalized peritonitis, with perforation, without abscess | |
| peritonitis NEC › localized › with › gangrene | K35.31 | Acute appendicitis with localized peritonitis and gangrene, without perforation | |
| peritonitis NEC › localized › with › perforation | K35.32 | Acute appendicitis with perforation, localized peritonitis, and gangrene, without abscess | |
| peritonitis NEC › generalized › with › abscess › with perforation or rupture | K35.211 | Acute appendicitis with generalized peritonitis, with perforation and abscess | |
| peritonitis NEC › generalized › with › abscess › following rupture or perforation of appendix NOS | K35.211 | Acute appendicitis with generalized peritonitis, with perforation and abscess | |
| peritonitis NEC › generalized › with › abscess › without perforation or rupture | K35.210 | Acute appendicitis with generalized peritonitis, without perforation, with abscess | |
| peritonitis NEC › localized › with › perforation › and abscess | K35.33 | Acute appendicitis with perforation, localized peritonitis, and gangrene, with abscess |
Appendicitis acute
| specified NEC | K35.890 | Other acute appendicitis without perforation or gangrene | |
| with › gangrene | K35.891 | Other acute appendicitis without perforation, with gangrene | |
| with › peritoneal abscess | K35.33 | Acute appendicitis with perforation, localized peritonitis, and gangrene, with abscess | |
| with › peritonitis NEC | K35.33 | Acute appendicitis with perforation, localized peritonitis, and gangrene, with abscess | |
| specified NEC › with gangrene | K35.891 | Other acute appendicitis without perforation, with gangrene | |
| with › peritonitis NEC › generalized | K35.209 | Acute appendicitis with generalized peritonitis, without abscess, unspecified as to perforation | |
| with › peritonitis NEC › localized | K35.30 | Acute appendicitis with localized peritonitis, without perforation or gangrene | |
| specified NEC › with gangrene › with localized peritonitis | K35.31 | Acute appendicitis with localized peritonitis and gangrene, without perforation | |
| with › peritonitis NEC › generalized › following rupture or perforation of appendix NOS | K35.201 | Acute appendicitis with generalized peritonitis, with perforation, without abscess | |
| with › peritonitis NEC › generalized › without rupture or perforation of appendix | K35.200 | Acute appendicitis with generalized peritonitis, without perforation or abscess | |
| with › peritonitis NEC › generalized › with › abscess | K35.219 | Acute appendicitis with generalized peritonitis, with abscess, unspecified as to perforation | |
| with › peritonitis NEC › generalized › with › perforation or rupture | K35.201 | Acute appendicitis with generalized peritonitis, with perforation, without abscess | |
| with › peritonitis NEC › localized › with › gangrene | K35.31 | Acute appendicitis with localized peritonitis and gangrene, without perforation | |
| with › peritonitis NEC › localized › with › perforation | K35.32 | Acute appendicitis with perforation, localized peritonitis, and gangrene, without abscess | |
| with › peritonitis NEC › generalized › with › abscess › with perforation or rupture | K35.211 | Acute appendicitis with generalized peritonitis, with perforation and abscess | |
| with › peritonitis NEC › generalized › with › abscess › following rupture or perforation of appendix NOS | K35.211 | Acute appendicitis with generalized peritonitis, with perforation and abscess | |
| with › peritonitis NEC › generalized › with › abscess › without perforation or rupture | K35.210 | Acute appendicitis with generalized peritonitis, without perforation, with abscess | |
| with › peritonitis NEC › localized › with › perforation › and abscess | K35.33 | Acute appendicitis with perforation, localized peritonitis, and gangrene, with abscess |
Index terms and codes are reproduced from the official ICD-10-CM FY2027 release. The Alphabetic Index is a finding aid — a code must always be verified in the Tabular List before it is reported. Data sources