2026 ICD-10-CM Diagnosis Code S00.551ASuperficial foreign body of lip, initial encounter

ICD-10-CM CodesS00–T88S00-S09S00

ICD-10-CM S00.551A
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

S00.551A is a billable ICD-10-CM diagnosis code for superficial foreign body of lip, 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 604 through 605, 963 through 965. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Superficial injury; contusion, initial encounter.

Code Identity

ICD-10-CM Code
S00.551A
Billable Status
Yes — Valid for Submission
Code Describes
Superficial foreign body of lip, initial encounter
Short Description
Superficial foreign body of lip, initial encounter
Same as the full description in the CMS dataset.
Parent Code
Superficial foreign body of lip

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS00-S09Injuries to the head
CategoryS00Superficial injury of head
This CodeS00.551ASuperficial foreign body of lip, initial encounter

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Foreign body in lip
  • Foreign body in skin of lip
  • Foreign body in skin of mouth
  • Superficial foreign body in lip
  • Superficial foreign body in mouth
  • Superficial foreign body of lip with infection
  • Superficial injury of lip
  • Superficial injury of lip with infection

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Superficial injury of head (S00). 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 INJ017
Superficial injury; contusion, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Foreign Bodies

If you've ever gotten a splinter or had sand in your eye, you've had experience with a foreign body. A foreign body is something that is stuck inside you but isn't supposed to be there. You may inhale or swallow a foreign body, or you may get one from an injury to almost any part of your body.

Read the full article at MedlinePlus

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

Convert S00.551A to ICD-9-CMHistory

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

ICD-9-CM
910.6 Foreign body head
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 S00.551AOverview

Is S00.551A (Superficial foreign body of lip) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report superficial foreign body of lip, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in S00.551A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for superficial foreign body of lip, such as an emergency visit or first evaluation.

What MS-DRG does S00.551A group to?

When superficial foreign body of lip, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 604, 605, 963, 964, 965, with relative weights from 0.9160 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of S00.551A?

Under the General Equivalence Mappings, superficial foreign body of lip, initial encounter converts to ICD-9-CM 910.6 (foreign body head). 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.