2026 ICD-10-CM Diagnosis Code L40.0Psoriasis vulgaris

ICD-10-CM Codes›L00–L99›L40-L45›L40

ICD-10-CM L40.0
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

L40.0 is a billable ICD-10-CM diagnosis code for psoriasis vulgaris. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 595 through 596. Coders also document this condition as actively extending plaque psoriasis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified inflammatory condition of skin.

Code Identity

ICD-10-CM Code
L40.0
Billable Status
Yes — Valid for Submission
Code Describes
Psoriasis vulgaris
Short Description
Psoriasis vulgaris
Same as the full description in the CMS dataset.
Parent Code
L40
Psoriasis

Code Classification

ChapterL00–L99Diseases of the skin and subcutaneous tissue
SectionL40-L45Papulosquamous disorders
CategoryL40Psoriasis
This CodeL40.0Psoriasis vulgaris

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Actively extending plaque psoriasis
  • Chronic large plaque psoriasis
  • Chronic small plaque psoriasis
  • Chronic stable plaque psoriasis
  • Plaque psoriasis
  • Plaque psoriasis with pustules
  • Psoriasis vulgaris

Tabular List NotesGuidance

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

Inclusion Terms

  • Nummular psoriasis
  • Plaque psoriasis

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.

    • Psoriasis
      • nummular
    • Psoriasis
      • plaque
    • Psoriasis
      • vulgaris

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

Clinical InformationClinical

  • Arthritis, Psoriatic

    a type of inflammatory arthritis associated with psoriasis, often involving the axial joints and the peripheral terminal interphalangeal joints. it is characterized by the presence of hla-b27-associated spondylarthropathy, and the absence of rheumatoid factor.

  • Guttate Psoriasis

    a skin condition, typically emerges suddenly and frequently occurs after an infection such as streptococcal infection. while prevalent among children, it can also manifest in young adults. its defining feature is the eruption of small, red, scaly patches that typically appear on the arms, legs, and torso.

  • Psoriasis

    a common genetically determined, chronic, inflammatory skin disease characterized by rounded erythematous, dry, scaling patches. the lesions have a predilection for nails, scalp, genitalia, extensor surfaces, and the lumbosacral region. accelerated epidermopoiesis is considered to be the fundamental pathologic feature in psoriasis.

  • Streptococcal Infections

    infections with bacteria of the genus streptococcus.

Patient EducationClinical

Psoriasis

Psoriasis is a skin disease that causes itchy or sore patches of thick, red skin with silvery scales. You usually get the patches on your elbows, knees, scalp, back, face, palms and feet, but they can show up on other parts of your body. Some people who have psoriasis also get a form of arthritis called psoriatic arthritis.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert L40.0 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
696.1 Other psoriasis
Approximate The match is approximate rather than exact.

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 L40.0Overview

Is L40.0 (Psoriasis) a billable code?

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

What MS-DRG does L40.0 group to?

When psoriasis vulgaris is the principal diagnosis on an inpatient stay, it groups to MS-DRG 595, 596, with relative weights from 1.0825 to 2.1207 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of L40.0?

Under the General Equivalence Mappings, psoriasis vulgaris converts to ICD-9-CM 696.1 (other psoriasis). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.