2026 ICD-10-CM Diagnosis Code L66.11Classic lichen planopilaris

ICD-10-CM Codes›L00–L99›L60-L75›L66

ICD-10-CM L66.11
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

L66.11 is a billable ICD-10-CM diagnosis code for classic lichen planopilaris. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 606 through 607. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified inflammatory condition of skin.

Code Identity

ICD-10-CM Code
L66.11
Billable Status
Yes — Valid for Submission
Code Describes
Classic lichen planopilaris
Short Description
Classic lichen planopilaris
Same as the full description in the CMS dataset.
Parent Code
L66.1
Lichen planopilaris

Code Classification

ChapterL00–L99Diseases of the skin and subcutaneous tissue
SectionL60-L75Disorders of skin appendages
CategoryL66Cicatricial alopecia [scarring hair loss]
This CodeL66.11Classic lichen planopilaris

Tabular List NotesGuidance

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

Inclusion Terms

  • Follicular lichen planus

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Lichen
      • planopilaris
        • classic
    • Lichen
      • planopilaris
        • follicular
    • Lichen
      • planus (chronicus)
        • follicular

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR SKN002
Other specified inflammatory condition of skin
Default principal diagnosis: inpatient Yes · outpatient Yes

Code History & ChangesHistory

Replacement L66.11 replaces the following previously assigned code(s):

  • L66.1 - Lichen planopilaris
FY 2025AddedAdded to the ICD-10-CM code setEffective October 1, 2024.
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About L66.11Overview

Is L66.11 (Lichen planopilaris) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report classic lichen planopilaris on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does L66.11 group to?

When classic lichen planopilaris is the principal diagnosis on an inpatient stay, it groups to MS-DRG 606, 607, with relative weights from 0.9064 to 1.5132 depending on complications. Higher weights mean higher Medicare reimbursement.

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.