2026 ICD-10-CM Diagnosis Code K12Stomatitis and related lesions

ICD-10-CM Codes›K00–K95›K00-K14›K12

ICD-10-CM K12
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

K12 is a non-billable ICD-10-CM category code for stomatitis and related lesions, so it cannot be submitted on claims. Use a more specific code from this category instead, such as K12.0, K12.1, K12.2, and K12.30.

Code Identity

ICD-10-CM Code
K12
Billable Status
No — Non-Billable Category
Code Describes
Stomatitis and related lesions
Chapter
K00-K14
Diseases of oral cavity and salivary glands

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK00-K14Diseases of oral cavity and salivary glands
CategoryK12Stomatitis and related lesions
This CodeK12Stomatitis and related lesions

Specific Coding for Stomatitis and related lesionsOverview

Non-specific codes like K12 require more characters. Use one of these billable codes instead:

  • Use K12.0 for Recurrent oral aphthae

  • Use K12.1 for Other forms of stomatitis

  • Use K12.2 for Cellulitis and abscess of mouth

  • K12.3 for Oral mucositis (ulcerative)

  • Use K12.30 for Oral mucositis (ulcerative), unspecified

  • Use K12.31 for Oral mucositis (ulcerative) due to antineoplastic therapy

  • Use K12.32 for Oral mucositis (ulcerative) due to other drugs

  • Use K12.33 for Oral mucositis (ulcerative) due to radiation

  • Use K12.39 for Other oral mucositis (ulcerative)

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Use Additional Code

  • code to identify:
  • alcohol abuse and dependence F10
  • exposure to environmental tobacco smoke Z77.22
  • exposure to tobacco smoke in the perinatal period P96.81
  • history of tobacco dependence Z87.891
  • occupational exposure to environmental tobacco smoke Z57.31
  • tobacco dependence F17
  • tobacco use Z72.0

Type 1 Excludes

  • cancrum oris A69.0
  • cheilitis K13.0
  • gangrenous stomatitis A69.0
  • herpesviral herpes simplex gingivostomatitis B00.2
  • noma A69.0

Patient EducationClinical

Mouth Disorders

Your mouth is one of the most important parts of your body. It has many different functions. It allows you to:

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Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About K12Overview

Is K12 (Stomatitis and related lesions) a billable code?

No. This is a category header that groups the codes for stomatitis and related lesions, and headers cannot be submitted on claims. Claims for stomatitis and related lesions need a more specific code from this category, such as K12.0, K12.1, and K12.2.