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A74.9

A74.9Chlamydial infection, unspecified

Billable / specific codeICD-10-CM

A74.9 is a billable, specific ICD-10-CM code for chlamydial infection, unspecified. It is valid for submission on a claim.

Inclusion terms

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

  • Chlamydiosis NOS

Other codes that can never be billed with A74.9

These codes carry an Excludes1 note pointing at A74.9. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading A74.9 alone.

  • A49Bacterial infection of unspecified site

Risk adjustment

A74.9 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 A74.9 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 A74.9.

  • Chlamydia, chlamydial
  • Disease, diseasedchlamydial
  • Infection, infected, infectiveChlamydia, chlamydial

Related codes at this level

Codes that share A74. If A74.9 is not quite right, the correct code is usually one of these.

Questions about A74.9

Is A74.9 a billable ICD-10-CM code?
Yes. A74.9 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does A74.9 sit in the tabular list?
Certain infectious and parasitic diseases (A00-B99), in the block Other diseases caused by chlamydiae (A70-A74).
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.