K66 – Other disorders of peritoneum

ICD-10-CM 2027 diagnosis code · Diseases of peritoneum, retroperitoneum and pelvis

Non-billable header

ICD-10-CM code K66
Code
K66 (claims format: K66)
Description
Other disorders of peritoneum
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
K65-K6A Diseases of peritoneum, retroperitoneum and pelvis

Billable codes under K66

K66 is a header code and cannot be used on claims. Choose the most specific code:

Notes for K66

Excludes2 (not included here):
  • ascites (R18.-)
  • peritoneal effusion (chronic) (R18.8)

Frequently asked questions

What is ICD-10 code K66?

K66 is the ICD-10-CM code for other disorders of peritoneum, in the block K65-K6A (Diseases of peritoneum, retroperitoneum and pelvis).

Is K66 a billable code?

No. K66 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.