2026 ICD-10-CM Diagnosis Code H05.012Cellulitis of left orbit

ICD-10-CM Codes›H00–H59›H00-H05›H05

ICD-10-CM H05.012
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

H05.012 is a billable ICD-10-CM diagnosis code for cellulitis of left orbit. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 121 through 122. Coders also document this condition as abscess of left orbit. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Oculofacial plastics and orbital conditions and Skin and subcutaneous tissue infections.

Code Identity

ICD-10-CM Code
H05.012
Billable Status
Yes — Valid for Submission
Code Describes
Cellulitis of left orbit
Short Description
Cellulitis of left orbit
Same as the full description in the CMS dataset.
Parent Code
H05.01
Cellulitis of orbit

Code Classification

ChapterH00–H59Diseases of the eye and adnexa
SectionH00-H05Disorders of eyelid, lacrimal system and orbit
CategoryH05Disorders of orbit
This CodeH05.012Cellulitis of left orbit

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Abscess of left orbit
  • Abscess of orbit
  • Abscess of periorbital region
  • Abscess of periorbital region of left eye
  • Cellulitis of left orbit
  • Orbital cellulitis
  • Subperiosteal abscess of orbit
  • Subperiosteal abscess of orbit of left eye

Clinical ClassificationClinical

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

CCSR EYE008
Oculofacial plastics and orbital conditions
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR SKN001
Skin and subcutaneous tissue infections
Default principal diagnosis: inpatient No · outpatient No

Clinical InformationClinical

  • Orbital Cellulitis

    inflammation of the loose connective tissues around the orbit, bony structure around the eyeball. it is characterized by pain; edema of the conjunctiva; swelling of the eyelids; exophthalmos; limited eye movement; and loss of vision.

  • Orbital Cellulitis

    inflammation of the eye tissues posterior to the orbital septum, and generally secondary to an infection spread from adjacent sinuses. signs and symptoms of the affected eye include sudden loss of vision, erythema, edema, decreased eye movement, and pain. treatment is conducted via intravenous antibiotics, observation, and surgical intervention when necessary.

  • Periorbital Cellulitis|Preseptal Cellulitis|Preseptal Cellulitis

    an acute infection of the anterior portion of the eyelid and surrounding tissues.

Patient EducationClinical

Cellulitis

Cellulitis is an infection of the skin and deep underlying tissues. Group A strep (streptococcal) bacteria are the most common cause. The bacteria enter your body when you get an injury such as a bruise, burn, surgical cut, or wound.

Read the full article at MedlinePlus

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

Convert H05.012 to ICD-9-CMHistory

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

ICD-9-CM
376.01 Orbital cellulitis
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 H05.012Overview

Is H05.012 (Cellulitis of orbit) a billable code?

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

What MS-DRG does H05.012 group to?

When cellulitis of left orbit is the principal diagnosis on an inpatient stay, it groups to MS-DRG 121, 122, with relative weights from 0.7858 to 1.1633 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of H05.012?

Under the General Equivalence Mappings, cellulitis of left orbit converts to ICD-9-CM 376.01 (orbital cellulitis). 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.