ICD-10-CM 2027
ICD-10 code for ascites
From the official ICD-10-CM alphabetic index entry “Ascites (abdominal)”. Page updated September 29, 2026.
About coding ascites
The ICD-10-CM code for ascites is R18.8 (Other ascites). The official index lists 12 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on R18.8.
Within R18, choose R18.8 (Other ascites) only when documentation doesn't support a more specific option: malignant ascites (R18.0).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
In MS-DRG v44.0, it is part of the grouping logic for DRG 947 (Signs and Symptoms with MCC, relative weight 1.261) and DRG 948 (Signs and Symptoms without MCC, relative weight 0.7835), in MDC 23 (Factors Influencing Health Status and Other Contacts with Health Services), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific ascites codes (official index)
- cardiac I50.810 — Right heart failure, unspecified
- chylous (nonfilarial) I89.8 — Other specified noninfective disorders of lymphatic vessels and lymph nodes
- filarial
- due to
- cirrhosis, alcoholic K70.31 — Alcoholic cirrhosis of liver with ascites
- hepatitis
- alcoholic K70.11 — Alcoholic hepatitis with ascites
- chronic active K73.2 — Chronic active hepatitis, not elsewhere classified
- with toxic liver disease K71.51 — Toxic liver disease with chronic active hepatitis with ascites
- S. japonicum B65.2 — Schistosomiasis due to Schistosoma japonicum
- heart I50.810 — Right heart failure, unspecified
- malignant R18.0 — Malignant ascites
- pseudochylous R18.8 — Other ascites
- syphilitic A52.74 — Syphilis of liver and other viscera
- tuberculous A18.31 — Tuberculous peritonitis
Common questions about ascites ICD-10 codes
What is the ICD-10 code for ascites?
- R18.8 — Other ascites. More specific codes apply when the documentation supports them: I50.810, I89.8, K70.31, K70.11 and others below.
What is the ICD-10 code for cardiac ascites?
- I50.810 — Right heart failure, unspecified.
What is the ICD-10 code for chylous ascites?
- I89.8 — Other specified noninfective disorders of lymphatic vessels and lymph nodes.
What is the ICD-10 code for heart ascites?
- I50.810 — Right heart failure, unspecified.
What is the ICD-10 code for malignant ascites?
- R18.0 — Malignant ascites.
What is the ICD-10 code for pseudochylous ascites?
- R18.8 — Other ascites.
What is the ICD-10 code for syphilitic ascites?
- A52.74 — Syphilis of liver and other viscera.
Is R18.8 billable?
- Yes. R18.8 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can R18.8 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict R18.8 as a principal diagnosis.
Is R18.8 a CC or MCC?
- R18.8 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.