L21 – Seborrheic dermatitis

ICD-10-CM 2027 diagnosis code · Dermatitis and eczema

Non-billable header

ICD-10-CM code L21
Code
L21 (claims format: L21)
Description
Seborrheic dermatitis
Billable
No – use a more specific code below
Valid for
Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter
12. Diseases of the skin and subcutaneous tissue (L00-L99)
Block
L20-L30 Dermatitis and eczema

Billable codes under L21

L21 is a header code and cannot be used on claims. Choose the most specific code:

Notes for L21

Excludes2 (not included here):
  • infective dermatitis (L30.3)
  • seborrheic keratosis (L82.-)

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

Block L20-L30

Excludes2 (not included here):
  • 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)
Notes:
  • In this block the terms dermatitis and eczema are used synonymously and interchangeably.

Frequently asked questions

What is ICD-10 code L21?

L21 is the ICD-10-CM code for seborrheic dermatitis, in the block L20-L30 (Dermatitis and eczema).

Is L21 a billable code?

No. L21 is a header code with more specific child codes; report one of the billable codes listed above.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.