2026 ICD-10-CM Diagnosis Code S01.302AUnspecified open wound of left ear, initial encounter
S01.302A is a billable ICD-10-CM diagnosis code for unspecified open wound of left ear, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 154 through 156, 963 through 965. Coders also document this condition as open wound of left ear. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Open wounds of head and neck, initial encounter.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Open wound of left ear
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Open wound of head (S01). Use the following options for the applicable episode of care:
- A - initial encounter
- D - subsequent encounter
- S - sequela
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Ear Disorders
Your ear has three main parts: outer, middle and inner. You use all of them in hearing. Sound waves come in through your outer ear. They reach your middle ear, where they make your eardrum vibrate. The vibrations are transmitted through three tiny bones, called ossicles, in your middle ear.
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Convert S01.302A to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S01.302AOverview
Is S01.302A (Unspecified open wound of left ear) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report unspecified open wound of left ear, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in S01.302A mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for unspecified open wound of left ear, such as an emergency visit or first evaluation.
What MS-DRG does S01.302A group to?
When unspecified open wound of left ear, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 154, 155, 156, 963, 964, 965, with relative weights from 0.6911 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of S01.302A?
Under the General Equivalence Mappings, unspecified open wound of left ear, initial encounter converts to ICD-9-CM 872.00 (opn wound extern ear NOS), 872.01 (open wound of auricle), and 872.02 (opn wound auditory canal). 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.
