Urinary Tract Infection ICD-10-CM Codes

N39.0 (urinary tract infection, site not specified) is the default code when the provider documents a UTI without identifying the organism or the specific site. It also covers recurrent UTI unless a more specific diagnosis is documented.

When the documentation names the site or condition, use the more specific category instead: N30.- for cystitis, N10 for acute pyelonephritis, and N34.- for urethritis. Do not assign N39.0 in addition to a specific-site code for the same episode.

Infections with a documented causative organism are often classified outside chapter 14, such as B37.4 for candidiasis of the urinary tract. Code the underlying infectious disease first when the provider links it to the urinary infection.