L21Header code — not billable

Seborrheic dermatitis

Chapter
12. Diseases of the skin and subcutaneous tissue
Category
L21
Effective date
October 1, 2026

Related codes in category L21

L21.0Seborrhea capitisYesL21.1Seborrheic infantile dermatitisYesL21.8Other seborrheic dermatitisYesL21.9Seborrheic dermatitis, unspecifiedYes

Frequently asked questions

What is ICD-10 code L21?

L21 is an ICD-10-CM diagnosis code for Seborrheic dermatitis.

Is L21 a billable code?

No. L21 is a category/header code, not billable on its own — use one of its more specific child codes instead.

What ICD-10-CM chapter is L21 in?

L21 falls under Chapter 12: Diseases of the skin and subcutaneous tissue.

When did L21 become effective?

L21 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.

What other codes are related to L21?

L21 belongs to category L21, which includes 4 other codes — see the related codes list on this page.

ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.