C66 – Malignant neoplasm of ureter

ICD-10-CM 2027 diagnosis code · Malignant neoplasms of urinary tract

Non-billable header

ICD-10-CM code C66
Code
C66 (claims format: C66)
Description
Malignant neoplasm of ureter
Billable
No – use a more specific code below
Valid for
Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter
2. Neoplasms (C00-D49)
Block
C64-C68 Malignant neoplasms of urinary tract

Billable codes under C66

C66 is a header code and cannot be used on claims. Choose the most specific code:

Notes for C66

Excludes1 (not coded here):
  • malignant neoplasm of ureteric orifice of bladder (C67.6)

Frequently asked questions

What is ICD-10 code C66?

C66 is the ICD-10-CM code for malignant neoplasm of ureter, in the block C64-C68 (Malignant neoplasms of urinary tract).

Is C66 a billable code?

No. C66 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.