K35 – Acute appendicitis
ICD-10-CM 2027 diagnosis code · Diseases of appendix
ICD-10-CM code
K35
- Code
K35(claims format:K35)- Description
- Acute appendicitis
- Billable
- No – use a more specific code below
- Valid for
- Dates of service October 1, 2026 – September 30, 2027 (FY2027)
- Chapter
- 11. Diseases of the digestive system (K00-K95)
- Block
- K35-K38 Diseases of appendix
Billable codes under K35
K35 is a header code and cannot be used on claims. Choose the most specific code:
- K35.2 – Acute appendicitis with generalized peritonitisHeader (more codes below)
- K35.3 – Acute appendicitis with localized peritonitisHeader (more codes below)
- K35.8 – Other and unspecified acute appendicitisHeader (more codes below)
Frequently asked questions
What is ICD-10 code K35?
K35 is the ICD-10-CM code for acute appendicitis, in the block K35-K38 (Diseases of appendix).
Is K35 a billable code?
No. K35 is a header code with more specific child codes; report one of the billable codes listed above.
Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.