Is ICD-10-CM code W57 billable?

No, W57 (Bitten or stung by nonvenomous insect and other nonvenomous arthropods) is a non-billable ICD-10-CM code. It must be coded to a more specific subcategory before it can be used for reimbursement.

What chapter does ICD-10-CM code W57 belong to?

W57 belongs to Chapter 20 of the ICD-10-CM tabular list: V00–Y99 (External Causes of Morbidity).

W57Not billable, use a more specific code below

Bitten or stung by nonvenomous insect and other nonvenomous arthropods

In Exposure to animate mechanical forces (W50-W64), chapter 20: External Causes of Morbidity

3 billable codes under W57: none are a CC or MCC; none map to an HCC.

Instructional notes

Excludes1: not coded here, use a different code

contact with venomous insects and arthropods (T63.2-, T63.3-, T63.4-)

Also applies, from Exposure to animate mechanical forces (W50-W64)

These notes sit on W50-W64 and apply to every code under it, including W57.

Excludes1: not coded here, use a different code

Toxic effect of contact with venomous animals and plants (T63.-)

Official coding guidelines

From the ICD-10-CM Official Guidelines for Coding and Reporting, FY 2027 (CMS and NCHS). Links open the PDF at the right page.

Covers how to report external cause codes (V00-Y99) describing cause, intent, place, activity, and status. They are never principal or first-listed, and reporting is voluntary unless required.

General External Cause Coding Guidelines (page 88)
Place of Occurrence Guideline (page 89)
Activity Code (page 89)
Place of Occurrence, Activity, and Status Codes Used with other External Cause Code (page 89)
If the Reporting Format Limits the Number of External Cause Codes (page 90)
Multiple External Cause Coding Guidelines (page 90)
Child and Adult Abuse Guideline (page 90)
Unknown or Undetermined Intent Guideline (page 91)

Read Section I.C.20 (page 87), 3 more topics

All codes under W57

W57 can't be used on a claim. Pick a billable code below; grey headings group them.

W57 MS-DRGs

This code does not group to an MS-DRG as a principal diagnosis.

About the condition

Plain-language background from MedlinePlus (National Library of Medicine), not coding guidance.

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. Travelers outside the United States may be at risk for malaria and other infections.

Spider Bites

Though many people are afraid of spiders, they rarely bite people unless threatened. Most spider bites are harmless. Occasionally, spider bites can cause allergic reactions. And bites by the venomous black widow and brown recluse spiders can be very dangerous to people.

Code history

Valid since FY2016, when ICD-10-CM took effect on October 1, 2015. No changes since.