Is J66 a billable ICD-10-CM code?

No. J66 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does J66 sit in the tabular list?

Diseases of the respiratory system (J00-J99), in the block Lung diseases due to external agents (J60-J70).

J66

J66 — Airway disease due to specific organic dust

Non-billable headerICD-10-CM

J66 is a non-billable header ICD-10-CM code for airway disease due to specific organic dust. It cannot be billed on its own: choose one of the more specific child codes below.

Excludes2 — not included here, but may coexist

The excluded condition is not part of this code, but a patient can have both. You may code both.

allergic alveolitis (J67.-)
asbestosis (J61)
bagassosis (J67.1)
farmer's lung (J67.0)
hypersensitivity pneumonitis due to organic dust (J67.-)
reactive airways dysfunction syndrome (J68.3)

Risk adjustment

J66 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.

Code to one of these instead J66

4 child codes. Green means billable.

Questions about J66

Is J66 a billable ICD-10-CM code?: No. J66 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does J66 sit in the tabular list?: Diseases of the respiratory system (J00-J99), in the block Lung diseases due to external agents (J60-J70).