R50.9

ICD-10Billable

Fever, unspecified

Official ICD-10-CM descriptor (FY2026)

Fever, unspecified

R50.9 is valid for submission on a claim — CMS flags it as a billable, specific code.

Inclusion terms

  • Fever NOS
  • Fever of unknown origin [FUO]
  • Fever with chills
  • Fever with rigors
  • Hyperpyrexia NOS
  • Persistent fever
  • Pyrexia NOS

Related codes in R50

Where this code sits

Parent code
R50

Krasyn AI Coder

Get code suggestions automatically as you type notes. Free for 50 analyses.

Install for Chrome — free

Source

ICD-10-CM FY2026. Centers for Medicare & Medicaid Services (CMS) / National Center for Health Statistics (NCHS), “2026 ICD-10-CM Code Descriptions in Tabular Order” (icd10cm_order_2026.txt). Download the original file from cms.gov. Public domain (US Government work). Descriptors, billable flags and instructional notes on this page are reproduced from that file without modification. Krasyn adds no clinical guidance.

Get codes automatically as you write notes. Krasyn AI Coder for Chrome — free for 50 analyses.Install free →