2027 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 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

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
Short Description
Stomatitis and related lesions
Same as the full description in the CMS dataset.
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)

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to K12: its own notes plus those printed at Chapter 11. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

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

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 11 (K00-K95) Diseases of the digestive system applies to 863 codes
  • 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)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

  • 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)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name K12, its category, or a range that includes it.

Excludes2 1

These codes carry an Excludes2 note naming K12: its condition is not part of those codes, and both may be reported when the patient has both.

  • K13 Other diseases of lip and oral mucosa
    stomatitis and related lesions (K12.-)

Use Additional Code 1

These codes say to use an additional code from the note, and K12 is one of the codes named.

  • L51 Erythema multiforme
    stomatitis (K12.-)

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:

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About K12Overview

What is the ICD-10 code for stomatitis and related lesions?

K12 is the ICD-10-CM category for stomatitis and related lesions, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

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.

Can K12 be reported with A69.0?

Not as a rule. The Excludes1 note on K12 lists "cancrum oris (A69.0)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

Does K12 need an additional code?

When the condition applies, yes. The Use Additional Code note reads: 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); and 2 more listed in the Instructional Notes section. The additional code is reported after K12.