K12 — Stomatitis and related lesions
Is K12 billable?
No — K12 is a non-billable header code. K12 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 8 billable codes beneath K12.
Billable codes under this header
- K12.0Recurrent oral aphthae
- K12.1Other forms of stomatitis
- K12.2Cellulitis and abscess of mouth
- K12.30Oral mucositis (ulcerative), unspecified
- K12.31Oral mucositis (ulcerative) due to antineoplastic therapy
- K12.32Oral mucositis (ulcerative) due to other drugs
- K12.33Oral mucositis (ulcerative) due to radiation
- K12.39Other oral mucositis (ulcerative)
K12 at a glance
| Code | K12 |
|---|---|
| Description | Stomatitis and related lesions |
| 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 K12 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Use additional code
Report an additional code alongside K12 to fully describe the condition. K12 is sequenced first.
- 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)
Excludes2 — not included here — inherited from Chapter 11
The conditions below are not part of K12, but a patient may have both at the same time. When documentation supports it, K12 and the excluded code may both be reported.
- 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)
What codes fall under K12? (4)
How long has K12 existed?
K12 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.
Which codes are confused with K12?
ICD-10-CM declares these codes mutually exclusive with K12 — exactly one of each pair can be correct for a given encounter.