2027 ICD-10-CM Diagnosis Code L21Seborrheic dermatitis

ICD-10-CM Codes›L00–L99›L20-L30›L21

ICD-10-CM L21
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

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
Short Description
Seborrheic dermatitis
Same as the full description in the CMS dataset.
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

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to L21: its own notes plus those printed at block L20-L30 and Chapter 12. A note printed at a category, block or chapter applies to every code under it.

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.

On L21 itself
  • infective dermatitis (L30.3)
  • seborrheic keratosis (L82.-)
From Block L20-L30 Dermatitis and eczema applies to 74 codes
  • chronic (childhood) granulomatous disease (D71-)
  • dermatitis gangrenosa (L08.0)
  • dermatitis herpetiformis (L13.0)
  • dry skin dermatitis (L85.3)
  • factitial dermatitis (L98.1)
  • perioral dermatitis (L71.0)
  • radiation-related disorders of the skin and subcutaneous tissue (L55-L59)
  • stasis dermatitis (I87.2)
From Chapter 12 (L00-L99) Diseases of the skin and subcutaneous tissue applies to 1,001 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)
  • lipomelanotic reticulosis (I89.8)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
  • systemic connective tissue disorders (M30-M36)
  • viral warts (B07.-)

Notes

General instructions on how these codes are used.

From Block L20-L30 Dermatitis and eczema applies to 74 codes
  • In this block the terms dermatitis and eczema are used synonymously and interchangeably.

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name L21, its category, or a range that includes it.

Excludes2 1

These codes carry an Excludes2 note naming L21: its condition is not part of those codes, and both may be reported when the patient has both.

  • L82 Seborrheic keratosis
    seborrheic dermatitis (L21.-)

Clinical InformationClinical

  • Dermatitis, Seborrheic

    a chronic inflammatory disease of the skin with unknown etiology. it is characterized by moderate erythema, dry, moist, or greasy (sebaceous gland) scaling and yellow crusted patches on various areas, especially the scalp, that exfoliate as dandruff. seborrheic dermatitis is common in children and adolescents with hiv infections.

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.

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 L21Overview

What is the ICD-10 code for seborrheic dermatitis?

L21 is the ICD-10-CM category for seborrheic dermatitis, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

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.