M05 – Rheumatoid arthritis with rheumatoid factor

ICD-10-CM 2027 diagnosis code · Inflammatory polyarthropathies

Non-billable header

ICD-10-CM code M05

Code: M05 (claims format: M05)
Description: Rheumatoid arthritis with rheumatoid factor
Billable: No – use a more specific code below
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 13. Diseases of the musculoskeletal system and connective tissue (M00-M99)
Block: M05-M14 Inflammatory polyarthropathies

Billable codes under M05

M05 is a header code and cannot be used on claims. Choose the most specific code:

M05.0 – Felty's syndromeHeader (more codes below)
M05.1 – Rheumatoid lung disease with rheumatoid arthritisHeader (more codes below)
M05.2 – Rheumatoid vasculitis with rheumatoid arthritisHeader (more codes below)
M05.3 – Rheumatoid heart disease with rheumatoid arthritisHeader (more codes below)
M05.4 – Rheumatoid myopathy with rheumatoid arthritisHeader (more codes below)
M05.5 – Rheumatoid polyneuropathy with rheumatoid arthritisHeader (more codes below)
M05.6 – Rheumatoid arthritis with involvement of other organs and systemsHeader (more codes below)
M05.7 – Rheumatoid arthritis with rheumatoid factor without organ or systems involvementHeader (more codes below)
M05.8 – Other rheumatoid arthritis with rheumatoid factorHeader (more codes below)
M05.9 – Rheumatoid arthritis with rheumatoid factor, unspecifiedBillable
M05.A – Abnormal rheumatoid factor and anti-citrullinated protein antibody with rheumatoid arthritisBillable

Notes for M05

Excludes1 (not coded here):

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

Frequently asked questions

What is ICD-10 code M05?

M05 is the ICD-10-CM code for rheumatoid arthritis with rheumatoid factor, in the block M05-M14 (Inflammatory polyarthropathies).

Is M05 a billable code?

No. M05 is a header code with more specific child codes; report one of the billable codes listed above.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.