C31.1Billable
Malignant neoplasm of ethmoidal sinus
- Chapter
- 2. Neoplasms
- Category
- C31
- Effective date
- October 1, 2026
Related codes in category C31
C31Malignant neoplasm of accessory sinusesC31.0Malignant neoplasm of maxillary sinusYesC31.2Malignant neoplasm of frontal sinusYesC31.3Malignant neoplasm of sphenoid sinusYesC31.8Malignant neoplasm of overlapping sites of accessory sinusesYesC31.9Malignant neoplasm of accessory sinus, unspecifiedYes
Frequently asked questions
What is ICD-10 code C31.1?
C31.1 is an ICD-10-CM diagnosis code for Malignant neoplasm of ethmoidal sinus.
Is C31.1 a billable code?
Yes. C31.1 is billable and specific enough to be used on a claim.
What ICD-10-CM chapter is C31.1 in?
C31.1 falls under Chapter 2: Neoplasms.
When did C31.1 become effective?
C31.1 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.
What other codes are related to C31.1?
C31.1 belongs to category C31, which includes 6 other codes — see the related codes list on this page.
ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.