R65.21 Severe sepsis with septic shock

The ICD-10-CM code for Severe sepsis with septic shock is R65.21 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

18: Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99)

Section

R50-R69: General symptoms and signs (R50-R69)

Category R65

7 codes (4 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to R65.21:

• Severe sepsis › with septic shock
• Shock › gram-negative
• Shock › endotoxic
• Shock › septic (due to severe sepsis)
• Sepsis (generalized) (unspecified organism) › severe › with septic shock
• Sepsis (generalized) (unspecified organism) › with › organ dysfunction (acute) (multiple) › with septic shock
• Infection, infected, infective (opportunistic) › with › organ dysfunction (acute) › with septic shock

U.S. Hospital Utilization

• An estimated 743,585 U.S. inpatient stays in 2023 included R65.21 among the documented diagnoses.
• 90 stays listed it as the principal diagnosis.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Official Coding Guidelines

Septic shock—sequencing and principal diagnosis restriction

2) Septic shock Septic shock generally refers to circulatory failure associated with severe sepsis, and therefore, it represents a type of acute organ dysfunction. For cases of septic shock, the code for the systemic infection should be sequenced first, followed by code R65.21, Severe sepsis with septic shock or code T81.12, Postprocedural septic shock. Any additional codes for the other acute organ dysfunctions should also be assigned. As noted in the sequencing instructions in the Tabular List, the code for septic shock cannot be assigned as a principal diagnosis.

Postprocedural septic shock: code T81.12-; do not assign R65.21

(c) Postprocedural infection and postprocedural septic shock If a postprocedural infection has resulted in postprocedural septic shock, assign the codes indicated above for sepsis due to a postprocedural infection, followed by code T81.12-, Postprocedural septic shock. Do not assign code R65.21, Severe sepsis with septic shock. Additional code(s) should be assigned for any acute organ dysfunction.

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool
• AHRQ — HCUP National Inpatient Sample, Frequencies by Diagnosis Code (2016–2023)