2026 ICD-10-CM Diagnosis Code K42.9Umbilical hernia without obstruction or gangrene

ICD-10-CM Codes›K00–K95›K40-K46›K42

ICD-10-CM K42.9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

K42.9 is a billable ICD-10-CM diagnosis code for umbilical hernia without obstruction or gangrene. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 393 through 395. Coders also document this condition as paraumbilical hernia. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Abdominal hernia.

Code Identity

ICD-10-CM Code
K42.9
Billable Status
Yes — Valid for Submission
Code Describes
Umbilical hernia without obstruction or gangrene
Short Description
Umbilical hernia without obstruction or gangrene
Same as the full description in the CMS dataset.
Parent Code
K42
Umbilical hernia

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK40-K46Hernia
CategoryK42Umbilical hernia
This CodeK42.9Umbilical hernia without obstruction or gangrene

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Paraumbilical hernia
  • Protruding umbilicus
  • Recurrent paraumbilical hernia
  • Recurrent umbilical hernia
  • Reducible umbilical hernia
  • Umbilical hernia

Tabular List NotesGuidance

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

Inclusion Terms

  • Umbilical hernia NOS

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.

    • Hernia, hernial(acquired) (recurrent)
      • umbilicus, umbilical

Clinical ClassificationClinical

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

CCSR DIG010
Abdominal hernia
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Gangrenous Umbilical Hernia

    a protrusion of necrotic tissue through the abdominal wall under the skin near the umbilicus.

  • Umbilical Hernia

    protrusion of the abdominal cavity contents through the abdominal wall at the umbilicus.

  • Umbilical Hernia with Obstruction without Mention of Gangrene

    the protrusion of contents of the abdominal cavity through the abdominal wall, at the site of the umbilicus, which results in obstruction, without mention of necrosis of the herniated contents.

  • Umbilical Hernia without Mention of Obstruction or Gangrene

    the protrusion of contents of the abdominal cavity through the abdominal wall, at the site of the umbilicus, without mention of obstruction or necrosis of the herniated contents.

Patient EducationClinical

Hernia

A hernia happens when part of an internal organ or tissue bulges through a weak area of muscle. Most hernias are in the abdomen.

Read the full article at MedlinePlus

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

Convert K42.9 to ICD-9-CMHistory

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

ICD-9-CM
553.1 Umbilical hernia
Exact Match The mapping is direct, with no qualifiers.

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 K42.9Overview

Is K42.9 (Umbilical hernia) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report umbilical hernia without obstruction or gangrene on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does K42.9 group to?

When umbilical hernia without obstruction or gangrene is the principal diagnosis on an inpatient stay, it groups to MS-DRG 393, 394, 395, with relative weights from 0.6490 to 1.5993 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of K42.9?

Under the General Equivalence Mappings, umbilical hernia without obstruction or gangrene converts to ICD-9-CM 553.1 (umbilical hernia). The mapping is a direct match.

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.