Is K81.9 a billable ICD-10-CM code?

Yes. K81.9 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does K81.9 sit in the tabular list?

Diseases of the digestive system (K00-K95), in the block Disorders of gallbladder, biliary tract and pancreas (K80-K87).

What cannot be coded together with K81.9?

K81.9 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above K81.9 (K81) and apply to it just the same.

K81.9

K81.9 — Cholecystitis, unspecified

Billable / specific codeICD-10-CM

K81.9 is a billable, specific ICD-10-CM code for cholecystitis, unspecified. It is valid for submission on a claim.

Excludes1 inherited from the categories above K81.9

These are not written on K81.9, but they bind it: a note on a category applies to every code beneath it. Billing K81.9 with anything listed here is a denial.

Written on K81 — Cholecystitis

cholecystitis with cholelithiasis (K80.-)

Other codes that can never be billed with K81.9

These codes carry an Excludes1 note pointing at K81.9. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading K81.9 alone.

K82.4Cholesterolosis of gallbladder

Risk adjustment

K81.9 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.

Medicare coverage

K81.9 is named in 1 Medicare coverage policy — 1 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A56421Billing and Coding: CT of the Abdomen and Pelvis

How K81.9 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 K81.9.

Cholecystitis
Infection, infected, infective›cystic duct

Code history

K81.9 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Related codes at this level

Codes that share K81. If K81.9 is not quite right, the correct code is usually one of these.

Questions about K81.9

Is K81.9 a billable ICD-10-CM code?: Yes. K81.9 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does K81.9 sit in the tabular list?: Diseases of the digestive system (K00-K95), in the block Disorders of gallbladder, biliary tract and pancreas (K80-K87).
What cannot be coded together with K81.9?: K81.9 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above K81.9 (K81) and apply to it just the same.