2026 ICD-10-CM Diagnosis Code B17.9Acute viral hepatitis, unspecified

ICD-10-CM CodesA00–B99B15-B19B17

ICD-10-CM B17.9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

B17.9 is a billable ICD-10-CM diagnosis code for acute viral hepatitis, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 441 through 443. Coders also document this condition as acute focal hepatitis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Hepatitis and Viral infection.

Code Identity

ICD-10-CM Code
B17.9
Billable Status
Yes — Valid for Submission
Code Describes
Acute viral hepatitis, unspecified
Short Description
Acute viral hepatitis, unspecified
Same as the full description in the CMS dataset.
Parent Code
Other acute viral hepatitis

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionB15-B19Viral hepatitis
CategoryB17Other acute viral hepatitis
This CodeB17.9Acute viral hepatitis, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute focal hepatitis
  • Acute fulminating viral hepatitis
  • Acute hepatic failure
  • Acute hepatic failure caused by hepatitis virus
  • Acute hepatitis
  • Acute infectious hepatitis
  • Acute viral hepatitis

Tabular List NotesGuidance

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

Inclusion Terms

  • Acute hepatitis NOS
  • Acute infectious hepatitis 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.

    • Hepatitis
      • acute
    • Hepatitis
      • acute
        • infectious
    • Hepatitis
      • acute
        • viral (see also, Hepatitis, viral)
    • Hepatitis
      • infectious, infective
        • acute (subacute)
    • Hepatitis
      • viral, virus
        • acute

Clinical ClassificationClinical

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

CCSR INF007
Hepatitis
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR INF008
Viral infection
Default principal diagnosis: inpatient No · outpatient No

Clinical InformationClinical

  • Acute Hepatitis

    acute inflammation of the liver.
  • Acute Hepatitis B Infection|Acute Hepatitis B

    a new infection by the hepatitis b virus, which can be transmitted by direct contact of infected blood with mucous membranes or open areas of the skin. signs and symptoms may include loss of appetite, joint and muscle pain, low-grade fever and stomach pain. two to six percent of adults progress to a chronic infection, while 90% of infants become chronically ill. a vaccine is available for those at risk.
  • Acute Hepatitis C Infection|Acute Hepatitis C

    a new infection by the hepatitis c virus, which can be detected in blood. signs and symptoms may include right upper quadrant abdominal pain, jaundice, dark urine, white stools and nausea. approximately 15%-25% individuals clear the virus from their bodies without treatment. 75%-85% individuals develop chronic hepatitis c. there are possible treatments depending on individual characteristics.
  • Acute Hepatitis E Infection|Acute Hepatitis E

    a new infection by the hepatitis e virus, which is usually spread by the fecal-oral route. signs and symptoms may include fever, fatigue, loss of appetite, nausea, vomiting, abdominal pain, jaundice, dark urine, clay-colored stools and joint pain. there is no specific anti-viral treatment, the infection resolves on its own.
  • Hepatitis A Infection|Acute Hepatitis A|Acute Hepatitis A|Hepatitis A|Hepatitis A

    acute inflammation of the liver caused by the hepatitis a virus. it is highly contagious and usually contracted through close contact with an infected individual or their feces, contaminated food or water.

Patient EducationClinical

Hepatitis

Hepatitis is inflammation of the liver. Inflammation is swelling that happens when tissues of the body are injured or infected. It can damage your liver. This swelling and damage can affect how well your liver functions.

The full article covers:

  • What is hepatitis?
  • What causes hepatitis?
  • How is viral hepatitis spread?
  • Who is at risk for hepatitis?
  • What are the symptoms of hepatitis?
  • What other problems can hepatitis cause?
  • How is hepatitis diagnosed?
  • What are the treatments for hepatitis?

Read the full article at MedlinePlus

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

Convert B17.9 to ICD-9-CMHistory

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

ICD-9-CM
070.9 Viral hepat NOS w/o coma
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 B17.9Overview

Is B17.9 (Other acute viral hepatitis) a billable code?

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

What MS-DRG does B17.9 group to?

When acute viral hepatitis, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 441, 442, 443, with relative weights from 0.6997 to 1.7947 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of B17.9?

Under the General Equivalence Mappings, acute viral hepatitis, unspecified converts to ICD-9-CM 070.9 (viral hepat NOS w/o coma). 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.