Sepsis ICD-10 code
The ICD-10-CM code for sepsis is A41.9 (sepsis, unspecified organism). It is billable and valid for submission on a claim. There are 16 related codes, and which one you use depends on what the documentation supports.
Also written as septicemia, septicaemia, blood infection, septic shock, urosepsis.
The mistake coders make here
Sepsis coding is sequencing-heavy: the underlying infection is coded first, and severe sepsis requires R65.2- plus a code for the associated organ dysfunction. A41.9 alone rarely tells the whole story.
Putting sepsis on a claim? Check the claim’s diagnosis codes free: Excludes1 conflicts, header codes and missing seventh characters, before it goes out.
ICD-10-CM codes for sepsis
13 of 16 are billable. Green means you can submit it as-is.
| Code | Use it when |
|---|---|
| A41.9 | Sepsis, unspecified organism |
| A41.51 | Sepsis due to Escherichia coli [E. coli] |
| A41.01 | Sepsis due to Methicillin susceptible Staphylococcus aureus |
| R65.20 | Severe sepsis without septic shock |
| R65.21 | Severe sepsis with septic shock |
| A41 | Other sepsisnot billable on its own |
| A41.89 | Other specified sepsis |
| A41.8 | Other specified sepsisnot billable on its own |
| A41.53 | Sepsis due to Serratia |
| A41.4 | Sepsis due to anaerobes |
| A41.81 | Sepsis due to Enterococcus |
| A41.59 | Other Gram-negative sepsis |
| A41.3 | Sepsis due to Hemophilus influenzae |
| A41.0 | Sepsis due to Staphylococcus aureusnot billable on its own |
| A41.54 | Sepsis due to Acinetobacter baumannii |
| A41.2 | Sepsis due to unspecified staphylococcus |
Once you have the code
- Check the whole claim: Excludes1 conflicts and missing seventh characters, free
- Denial codes explained: what CO-16, CO-97 and the rest actually mean
- Decision guides: walk a chart note to a code, guideline cited
- Everything here that is free, and the one thing no free tool includes
Sepsis, severe sepsis and septic shock are three different code sets
This is the distinction everything else rests on, and the words are not interchangeable. Sepsis on its own is a single code for the underlying infection: A41.9 when the organism is not documented, or a specific code such as A41.51 for sepsis due to E. coli. Severe sepsis means sepsis with associated acute organ dysfunction, and it is never a single code: you need the infection code, then R65.20, then a code for each organ dysfunction documented. Septic shock is severe sepsis with circulatory failure, and it is R65.21 in place of R65.20: still alongside the infection code and the organ dysfunction codes, never instead of them. R65.2- can never be a principal diagnosis and cannot be assigned on its own at all.
The sequencing rule, in the order you apply it
Code the underlying systemic infection first: that is the principal diagnosis when sepsis is the reason for admission. Then R65.20 or R65.21 if severe sepsis or septic shock is documented. Then a code for every acute organ dysfunction the chart identifies: acute kidney failure, acute respiratory failure, encephalopathy, hepatic failure, and so on. The organ dysfunction codes are what turn a documented severe sepsis into a coded one, and leaving them off is the most common way a severe sepsis admission gets coded as ordinary sepsis. Where the infection is localized as well (a UTI, a pneumonia, a wound infection), that localized infection is coded too, after the sepsis codes, not instead of them.
Urosepsis is not a code, and it is not sepsis
ICD-10-CM has no code for urosepsis and no index entry that takes you to one. The term is used clinically to mean anything from a UTI to genuine sepsis of urinary origin, which is exactly why it cannot be coded: it does not name a single condition. If the chart says urosepsis and nothing else, that is a query, not a coding decision. If the provider confirms sepsis, code the sepsis (A41.-) first and then the urinary tract infection (N39.0 or a more specific code). If the provider confirms only a urinary tract infection, that is what you code, and there is no sepsis code at all. The same applies to any ICD-9-era habit: septicemia as a standalone concept does not survive into ICD-10-CM the way it read in 038.-.
Suspected, ruled out, and 'possible' sepsis
Inpatient and outpatient rules diverge here and it matters. On an inpatient record, a diagnosis documented as suspected, possible or probable at the time of discharge is coded as if it existed, so suspected sepsis still gets the sepsis code. On an outpatient record, it is not: you code the signs and symptoms that prompted the workup instead, such as fever or tachycardia. Where sepsis is documented as ruled out, neither setting codes it; code the condition that was actually found, and consider whether an observation code applies.
Sepsis following a procedure, and sepsis due to a device
Post-procedural sepsis is coded from the complication chapter first, not from A41 first. Sequence the postprocedural infection code: T81.44- for sepsis following a procedure, or the device-specific code where a device is implicated, such as T80.211- for bloodstream infection due to a central venous catheter, then the specific infection code, then R65.2- and the organ dysfunction codes if severe sepsis or septic shock is documented. Getting this order wrong is a common inpatient audit finding, because the complication code is what tells the payer the infection was procedure-related.
Common questions
- What is the ICD-10 code for sepsis with septic shock?
- At least three codes, never one. Code the underlying infection first (A41.9 if no organism is documented, or the specific organism code), then R65.21 for severe sepsis with septic shock, then a code for each acute organ dysfunction documented. R65.21 already includes the severe sepsis, so R65.20 is not also assigned, and R65.21 can never stand alone or be the principal diagnosis.
- What is the ICD-10 code for a UTI with sepsis?
- Sequence the sepsis first: A41.9, or the organism-specific code such as A41.51 for E. coli. Then N39.0 for the urinary tract infection, site not specified. If severe sepsis or septic shock is documented, R65.20 or R65.21 goes between them, followed by the organ dysfunction codes. Do not reach for a urosepsis code: there is not one.
- Is severe sepsis coded even when the organ dysfunction has its own code?
- Yes, and both are required. R65.20 is what identifies the case as severe sepsis; the organ dysfunction code is what says which organ failed. Assigning only the organ dysfunction code loses the severe sepsis entirely, and assigning only R65.20 leaves it unsupported. The guideline expects the infection code, R65.2-, and every documented acute organ dysfunction.
- What replaced the ICD-9 septic shock and urosepsis codes?
- ICD-9's 785.52 for septic shock became R65.21, which is now severe sepsis with septic shock and carries the sequencing rules above. Urosepsis had no clean ICD-9 code either, and ICD-10-CM removed the ambiguity entirely by having no code and no index entry for it: the term now always requires a provider query rather than a coding judgement.