2026 ICD-10-CM Diagnosis Code L21Seborrheic dermatitis

ICD-10-CM Codes›L00–L99›L20-L30›L21

ICD-10-CM L21
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

L21 is a non-billable ICD-10-CM category code for seborrheic dermatitis, so it cannot be submitted on claims. Use a more specific code from this category instead, such as L21.0, L21.1, L21.8, and L21.9.

Code Identity

ICD-10-CM Code
L21
Billable Status
No — Non-Billable Category
Code Describes
Seborrheic dermatitis
Chapter
L20-L30
Dermatitis and eczema

Code Classification

ChapterL00–L99Diseases of the skin and subcutaneous tissue
SectionL20-L30Dermatitis and eczema
CategoryL21Seborrheic dermatitis
This CodeL21Seborrheic dermatitis

Specific Coding for Seborrheic dermatitisOverview

Non-specific codes like L21 require more characters. Use one of these billable codes instead:

  • Use L21.0 for Seborrhea capitis

  • Use L21.1 for Seborrheic infantile dermatitis

  • Use L21.8 for Other seborrheic dermatitis

  • Use L21.9 for Seborrheic dermatitis, unspecified

Tabular List NotesGuidance

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

Type 2 Excludes

  • infective dermatitis L30.3
  • seborrheic keratosis L82

Patient EducationClinical

Dandruff, Cradle Cap, and Other Scalp Conditions

Your scalp is the skin on the top of your head. Unless you have hair loss, hair grows on your scalp. Different skin problems can affect your scalp.

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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 L21Overview

Is L21 (Seborrheic dermatitis) a billable code?

No. This is a category header that groups the codes for seborrheic dermatitis, and headers cannot be submitted on claims. Claims for seborrheic dermatitis need a more specific code from this category, such as L21.0, L21.1, and L21.8.