2026 ICD-10-CM Diagnosis Code S40.261AInsect bite (nonvenomous) of right shoulder, initial encounter
S40.261A is a billable ICD-10-CM diagnosis code for insect bite (nonvenomous) of right shoulder, 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 606 through 607, 963 through 965. Coders also document this condition as insect bite, nonvenomous, of shoulder. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Superficial injury; contusion, initial encounter.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Insect bite, nonvenomous, of shoulder
- Nonvenomous insect bite of right shoulder with infection
- Nonvenomous insect bite of shoulder with infection
- Wound of right shoulder due to nonvenomous insect bite
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Superficial injury of shoulder and upper arm (S40). 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
Insect Bites and Stings
Most insect bites are harmless, though they sometimes cause discomfort. Bee, wasp, and hornet stings and fire ant bites usually hurt. Mosquito and flea bites usually itch. Insects can also spread diseases. In the United States, some mosquitoes spread West Nile virus.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert S40.261A to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S40.261AOverview
Is S40.261A (Insect bite (nonvenomous) of right shoulder) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report insect bite (nonvenomous) of right shoulder, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in S40.261A mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for insect bite (nonvenomous) of right shoulder, such as an emergency visit or first evaluation.
What MS-DRG does S40.261A group to?
When insect bite (nonvenomous) of right shoulder, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 606, 607, 963, 964, 965, with relative weights from 0.9064 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of S40.261A?
Under the General Equivalence Mappings, insect bite (nonvenomous) of right shoulder, initial encounter converts to ICD-9-CM 912.4 (insect bite shoulder/arm). 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.
