MCMCB Pro
B09

B09Unspecified viral infection characterized by skin and mucous membrane lesions

Billable / specific codeICD-10-CM

B09 is a billable, specific ICD-10-CM code for unspecified viral infection characterized by skin and mucous membrane lesions. It is valid for submission on a claim.

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

  • Viral enanthema NOS
  • Viral exanthema NOS

Risk adjustment

B09 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

How B09 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to B09.

  • Enanthema, viral
  • Roseola
  • Encephalitispostexanthematous NEC
  • Exanthem, exanthemaviral, virus
  • Keratoconjunctivitisin exanthema
  • Infection, infected, infectivevirus, viral NOSexanthem NOS
  • Keratitisinexanthema

Questions about B09

Is B09 a billable ICD-10-CM code?
Yes. B09 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does B09 sit in the tabular list?
Certain infectious and parasitic diseases (A00-B99), in the block Viral infections characterized by skin and mucous membrane lesions (B00-B09).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.