S21.309Header code — not billable

Unspecified open wound of unspecified front wall of thorax with penetration into thoracic cavity

Short description: Unsp opn wnd unsp front wall of thorax w penet thor cavity

Chapter
19. Injury, poisoning and certain other consequences of external causes
Category
S21
Effective date
October 1, 2026

Related codes in category S21

S21Open wound of thoraxS21.0Open wound of breastS21.00Unspecified open wound of breastS21.001Unspecified open wound of right breastS21.001AUnspecified open wound of right breast, initial encounterYesS21.001DUnspecified open wound of right breast, subsequent encounterYesS21.001SUnspecified open wound of right breast, sequelaYesS21.002Unspecified open wound of left breastS21.002AUnspecified open wound of left breast, initial encounterYesS21.002DUnspecified open wound of left breast, subsequent encounterYesS21.002SUnspecified open wound of left breast, sequelaYesS21.009Unspecified open wound of unspecified breast

Frequently asked questions

What is ICD-10 code S21.309?

S21.309 is an ICD-10-CM diagnosis code for Unspecified open wound of unspecified front wall of thorax with penetration into thoracic cavity.

Is S21.309 a billable code?

No. S21.309 is a category/header code, not billable on its own — use one of its more specific child codes instead.

What ICD-10-CM chapter is S21.309 in?

S21.309 falls under Chapter 19: Injury, poisoning and certain other consequences of external causes.

When did S21.309 become effective?

S21.309 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.

What other codes are related to S21.309?

S21.309 belongs to category S21, which includes 12 other codes — see the related codes list on this page.

ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.