2026 ICD-10-CM Diagnosis Code L05.01Pilonidal cyst with abscess

ICD-10-CM CodesL00–L99L00-L08L05

ICD-10-CM L05.01
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

L05.01 is a billable ICD-10-CM diagnosis code for pilonidal cyst with abscess. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 602 through 603. Coders also document this condition as pilonidal abscess. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Skin and subcutaneous tissue infections.

Code Identity

ICD-10-CM Code
L05.01
Billable Status
Yes — Valid for Submission
Code Describes
Pilonidal cyst with abscess
Short Description
Pilonidal cyst with abscess
Same as the full description in the CMS dataset.
Parent Code
Pilonidal cyst and sinus with abscess

Code Classification

ChapterL00–L99Diseases of the skin and subcutaneous tissue
SectionL00-L08Infections of the skin and subcutaneous tissue
CategoryL05Pilonidal cyst and sinus
This CodeL05.01Pilonidal cyst with abscess

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Pilonidal abscess
  • Pilonidal abscess of natal cleft
  • Pilonidal disease of natal cleft

Tabular List NotesGuidance

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

Inclusion Terms

  • Pilonidal abscess
  • Pilonidal dimple with abscess
  • Postanal dimple with abscess

Type 2 Excludes

  • congenital sacral dimple Q82.6
  • parasacral dimple Q82.6

Index to Diseases and InjuriesGuidance

External Cause of Injuries IndexGuidance

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

    • Abscess(connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic)
      • pilonidal
    • Cyst(colloid) (mucous) (simple) (retention)
      • pilonidal (infected) (rectum)
        • with abscess

Clinical ClassificationClinical

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

CCSR SKN001
Skin and subcutaneous tissue infections
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Abscess

An abscess is a pocket of pus. You can get an abscess almost anywhere in your body. When an area of your body becomes infected, your body's immune system tries to fight the infection. White blood cells go to the infected area, collect within the damaged tissue, and cause inflammation. During this process, pus forms.

Read the full article at MedlinePlus

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

Convert L05.01 to ICD-9-CMHistory

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

ICD-9-CM
685.0 Pilonidal cyst w abscess
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 L05.01Overview

Is L05.01 (Pilonidal cyst and sinus with abscess) a billable code?

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

What MS-DRG does L05.01 group to?

When pilonidal cyst with abscess is the principal diagnosis on an inpatient stay, it groups to MS-DRG 602, 603, with relative weights from 0.8709 to 1.4213 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of L05.01?

Under the General Equivalence Mappings, pilonidal cyst with abscess converts to ICD-9-CM 685.0 (pilonidal cyst w abscess). The mapping is approximate, so confirm the match fits the documentation.

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.