2026 ICD-10-CM Diagnosis Code S20.369SInsect bite (nonvenomous) of unspecified front wall of thorax, sequela

ICD-10-CM CodesS00–T88S20-S29S20

ICD-10-CM S20.369S
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

S20.369S is a billable ICD-10-CM diagnosis code for insect bite (nonvenomous) of unspecified front wall of thorax, sequela. The 7th character S marks it as a sequela code, which reports a problem that remains after the original condition has resolved. 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. The code is exempt from POA reporting. Coders also document this condition as insect bite, nonvenomous, of chest wall. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Injury, sequela.

Code Identity

ICD-10-CM Code
S20.369S
Billable Status
Yes — Valid for Submission
Code Describes
Insect bite (nonvenomous) of unspecified front wall of thorax, sequela
Short Description
Insect bite of unsp front wall of thorax, sequela
Parent Code
Insect bite (nonvenomous) of unspecified front wall of thorax

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS20-S29Injuries to the thorax
CategoryS20Superficial injury of thorax
This CodeS20.369SInsect bite (nonvenomous) of unspecified front wall of thorax, sequela

Present on Admission (POA)Billing

S20.369S is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Insect bite, nonvenomous, of chest wall
  • Nonvenomous insect bite of chest wall with infection
  • Nonvenomous insect bite of chest wall without infection
  • Nonvenomous insect bite of trunk without infection
  • Superficial injury of chest wall without infection

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Superficial injury of thorax (S20). 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 INJ073
Injury, sequela
Default principal diagnosis: inpatient Yes · outpatient Yes

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 S20.369S to ICD-9-CMHistory

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

ICD-9-CM
906.2 Late eff superficial inj
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 S20.369SOverview

Is S20.369S a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report insect bite (nonvenomous) of unspecified front wall of thorax, sequela on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character S in S20.369S mean?

The final character S makes this a sequela code: it reports a lingering problem that remains after the insect bite (nonvenomous) of unspecified front wall of thorax itself has resolved, not the original event.

What MS-DRG does S20.369S group to?

When insect bite (nonvenomous) of unspecified front wall of thorax, sequela is the principal diagnosis on an inpatient stay, it groups to MS-DRG 604, 605, with relative weights from 0.9160 to 1.4721 depending on complications. Higher weights mean higher Medicare reimbursement.

Is S20.369S exempt from POA reporting?

Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for insect bite (nonvenomous) of unspecified front wall of thorax, sequela on inpatient claims.

What is the ICD-9 equivalent of S20.369S?

Under the General Equivalence Mappings, insect bite (nonvenomous) of unspecified front wall of thorax, sequela converts to ICD-9-CM 906.2 (late eff superficial inj). 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.