2026 ICD-10-CM Diagnosis Code S15.029AMajor laceration of unspecified carotid artery, initial encounter

ICD-10-CM Codes›S00–T88›S10-S19›S15

ICD-10-CM S15.029A
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

S15.029A is a billable ICD-10-CM diagnosis code for major laceration of unspecified carotid artery, 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 913 through 914, 963 through 965. The code is flagged as an unspecified code, since codes identifying laterality exist in the same family. Coders also document this condition as complete transection of carotid artery. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Injury to blood vessels, initial encounter.

Code Identity

ICD-10-CM Code
S15.029A
Billable Status
Yes — Valid for Submission
Code Describes
Major laceration of unspecified carotid artery, initial encounter
Short Description
Major laceration of unspecified carotid artery, init encntr
Parent Code
S15.029
Major laceration of unspecified carotid artery

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS10-S19Injuries to the neck
CategoryS15Injury of blood vessels at neck level
This CodeS15.029AMajor laceration of unspecified carotid artery, initial encounter

Code EditsBilling

Medicare Code Editor checks that affect claim validity for S15.029A.

Unspecified codes
Unspecified codes exist in the ICD-10-CM classification for circumstances when documentation in the medical record does not provide the level of detail needed to support reporting a more specific code. However, in the inpatient setting, there should generally be very limited and rare circumstances for which the laterality (right, left, bilateral) of a condition is unable to be documented and reported. The following pages contain the list of unspecified ICD-10-CM diagnosis codes for which there is a more specific code to identify laterality (right, left, bilateral) within that code family.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Complete transection of carotid artery
  • Laceration of carotid artery
  • Major laceration of carotid artery
  • Transection of carotid artery

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Injury of blood vessels at neck level (S15). 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.

CCSR INJ016
Injury to blood vessels, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Wounds and Injuries

An injury is damage to your body. It is a general term that refers to harm caused by accidents, falls, hits, weapons, and more. In the U.S., millions of people injure themselves every year. These injuries range from minor to life-threatening.

Read the full article at MedlinePlus

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

Convert S15.029A to ICD-9-CMHistory

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

ICD-9-CM
900.00 Injur carotid artery NOS
Approximate The match is approximate rather than exact.
ICD-9-CM
900.01 Inj common carotid arter
Approximate The match is approximate rather than exact.
ICD-9-CM
900.02 Inj external carotid art
Approximate The match is approximate rather than exact.
ICD-9-CM
900.03 Inj internal carotid art
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 S15.029AOverview

Is S15.029A (Major laceration of unspecified carotid artery) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report major laceration of unspecified carotid artery, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in S15.029A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for major laceration of unspecified carotid artery, such as an emergency visit or first evaluation.

What MS-DRG does S15.029A group to?

When major laceration of unspecified carotid artery, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 913, 914, 963, 964, 965, with relative weights from 0.8855 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of S15.029A?

Under the General Equivalence Mappings, major laceration of unspecified carotid artery, initial encounter converts to ICD-9-CM 900.00 (injur carotid artery NOS), 900.01 (inj common carotid arter), and 900.02 (inj external carotid art). 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.