C18 — Malignant neoplasm of colon

Not billable

Is C18 billable?

No — C18 is a non-billable header code. C18 groups more specific codes and cannot be submitted on a claim. A valid ICD-10-CM code must be reported at the highest level of specificity available in its branch. Select one of the 10 billable codes beneath C18.

Billable codes under this header

C18 at a glance

Code	C18
Description	Malignant neoplasm of colon
Billable	No — header code
Code set	ICD-10-CM FY2027
Valid for encounters	October 1, 2026 – September 30, 2027

Excludes1 — never code together

The conditions below can never be reported together with C18 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.

malignant carcinoid tumors of the colon (C7A.02-)

Excludes1 — never code together — inherited from C15-C26

The conditions below can never be reported together with C18 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.

Kaposi's sarcoma of gastrointestinal sites (C46.4)

Excludes2 — not included here — inherited from C15-C26

The conditions below are not part of C18, but a patient may have both at the same time. When documentation supports it, C18 and the excluded code may both be reported.

gastrointestinal stromal tumors (C49.A-)

What codes fall under C18? (10)

How long has C18 existed?

C18 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.

Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.