Is ICD-10-CM code K66 billable?

No, K66 (Other disorders of peritoneum) is a non-billable ICD-10-CM code. It must be coded to a more specific subcategory before it can be used for reimbursement.

What chapter does ICD-10-CM code K66 belong to?

K66 belongs to Chapter 11 of the ICD-10-CM tabular list: K00–K95 (Diseases of the Digestive System).

K66Non-billable

Other disorders of peritoneum

Diseases of the Digestive System·Diseases of peritoneum and retroperitoneum (K65-K68)·category·FY 2026

Use a more specific code (4 billable)

K66.0Peritoneal adhesions (postprocedural) (postinfection)K66.1Hemoperitoneum K66.8Other specified disorders of peritoneum K66.9Disorder of peritoneum, unspecified

CH11 Parent Instructions

Excludes2(Not included here. Code separately if applicable.)

certain conditions originating in the perinatal period (P04-P96)
certain infectious and parasitic diseases (A00-B99)
complications of pregnancy, childbirth and the puerperium (O00-O9A)
congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
endocrine, nutritional and metabolic diseases (E00-E88)
injury, poisoning and certain other consequences of external causes (S00-T88)
neoplasms (C00-D49)
symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Instructional Notes

Excludes2(Not included here. Code separately if applicable.)

ascites (R18.-)
peritoneal effusion (chronic) (R18.8)

Clinical Hierarchy

BillableHas subcodes

CH11Diseases of the digestive system (K00-K95)

K65-K68Diseases of peritoneum and retroperitoneum (K65-K68)

K66Other disorders of peritoneumNot billable

K66.0Peritoneal adhesions (postprocedural) (postinfection)Billable

K66.1HemoperitoneumBillable

K66.8Other specified disorders of peritoneumBillable

K66.9Disorder of peritoneum, unspecifiedBillable

MS-DRG Classification

2026

No direct MS-DRG triggers identified.