Is M05 a billable ICD-10-CM code?

No. M05 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does M05 sit in the tabular list?

Diseases of the musculoskeletal system and connective tissue (M00-M99), in the block Inflammatory polyarthropathies (M05-M14).

What cannot be coded together with M05?

M05 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.

M05

M05 — Rheumatoid arthritis with rheumatoid factor

Non-billable headerICD-10-CM

M05 is a non-billable header ICD-10-CM code for rheumatoid arthritis with rheumatoid factor. It cannot be billed on its own: choose one of the more specific child codes below.

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

rheumatic fever (I00)
juvenile rheumatoid arthritis (M08.-)
rheumatoid arthritis of spine (M45.-)

Other codes that can never be billed with M05

These codes carry an Excludes1 note pointing at M05. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading M05 alone.

L95Vasculitis limited to skin, not elsewhere classified
M08Juvenile arthritis
R76.81Abnormal rheumatoid factor and anti-citrullinated protein antibody without rheumatoid arthritis
G63Polyneuropathy in diseases classified elsewhere
G73.7Myopathy in diseases classified elsewhere
I09.9Rheumatic heart disease, unspecified
I32Pericarditis in diseases classified elsewhere
I39Endocarditis and heart valve disorders in diseases classified elsewhere

Risk adjustment

M05 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 M05

11 child codes. Green means billable.

Questions about M05

Is M05 a billable ICD-10-CM code?: No. M05 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does M05 sit in the tabular list?: Diseases of the musculoskeletal system and connective tissue (M00-M99), in the block Inflammatory polyarthropathies (M05-M14).
What cannot be coded together with M05?: M05 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.