2026 ICD-10-CM Diagnosis Code K13.21Leukoplakia of oral mucosa, including tongue
ICD-10-CM Codes›K00–K95›K00-K14›K13
- Billable — Valid for Submission
- Not Chronic
K13.21 is a billable ICD-10-CM diagnosis code for leukoplakia of oral mucosa, including tongue. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 157 through 159. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Any dental condition including traumatic injury, Diseases of mouth; excluding dental, and Nontraumatic dental conditions.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Dysplastic oral leukoplakia
- Homogenous oral leukoplakia
- Hyperplasia of gingiva
- Leukoplakia
- Leukoplakia of buccal mucosa
- Leukoplakia of gingiva
- Leukoplakia of lips
- Leukoplakia of oral mucosa
- Leukoplakia of oral mucosa and tongue
- Leukoplakia of tongue
- Leukoplakia of tongue associated with HIV disease
- Oral leukoplakia caused by sanguinarine
- Oral syphilis
- Palmoplantar keratoderma with leukoplakia
- Proliferative verrucous oral leukoplakia
- Speckled oral leukoplakia
- Syphilitic leukoplakia of tongue
- Syphilitic oral leukoplakia
- Ulcerated oral leukoplakia
- Verrucous oral leukoplakia
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Leukokeratosis of oral mucosa
- Leukoplakia of gingiva, lips, tongue
Type 1 Excludes
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
- Leukokeratosis - See Also: Leukoplakia;
- mouth - K13.21
- oral mucosa - K13.21
- tongue - K13.21
External Cause of Injuries IndexGuidance
References for this code in the External Cause of Injuries Index.
- Leukokeratosis
- mouth
- Leukokeratosis
- oral mucosa
- Leukokeratosis
- tongue
- Leukoplakia
- buccal
- Leukoplakia
- gingiva
- Leukoplakia
- lip
- Leukoplakia
- mouth
- Leukoplakia
- oral epithelium, including tongue (mucosa)
- Leukoplakia
- palate
- Leukoplakia
- tongue
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Leukoplakia
a white patch lesion found on a mucous membrane that cannot be scraped off. leukoplakia is generally considered a precancerous condition, however its appearance may also result from a variety of hereditary diseases.Leukoplakia, Hairy
epithelial hyperplasia of the oral mucosa associated with epstein-barr virus (herpesvirus 4, human) and found almost exclusively in persons with hiv infection. the lesion consists of a white patch that is often corrugated or hairy.Leukoplakia, Oral
a white patch seen on the oral mucosa. it is considered a premalignant condition and is often tobacco-induced. when evidence of epstein-barr virus is present, the condition is called hairy leukoplakia (leukoplakia, hairy).Leukoplakia of Buccal Mucosa
a clinical term that indicates the presence of a white patch on the buccal mucosa in the mouth which cannot be characterized as any other disease. it may be a precancerous condition and in most cases histologic examination reveals keratosis.Speckled Oral Leukoplakia
non-homogenous leukoplakia on the oral mucosa. it is associated with a high risk for malignant transformation.Palmoplantar Keratoderma with Leukoplakia
a hereditary syndrome this is characterized by palmoplantar keratoderma accompanied by leukoplakia and may be associated with a high lifetime risk of esophageal cancer, as seen in howel-evans syndrome.Hairy Leukoplakia of Tongue
an epithelial hyperplasia on the surface of the tongue associated with epstein-barr virus and found almost exclusively in persons with hiv infection. the lesion consists of a white patch that is often corrugated or hairy.Leukoplakia of Tongue
a clinical term that indicates the presence of a white patch on the surface of the tongue which cannot be characterized as any other disease. it may be a precancerous condition and in most cases histologic examination reveals keratosis.
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
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Convert K13.21 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About K13.21Overview
Is K13.21 a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report leukoplakia of oral mucosa, including tongue on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does K13.21 group to?
When leukoplakia of oral mucosa, including tongue is the principal diagnosis on an inpatient stay, it groups to MS-DRG 157, 158, 159, with relative weights from 0.7085 to 1.7168 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of K13.21?
Under the General Equivalence Mappings, leukoplakia of oral mucosa, including tongue converts to ICD-9-CM 528.6 (leukoplakia oral mucosa). The mapping is approximate, so confirm the match fits the documentation.
Footnotes
[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.
