ICD-10-CM 2027
ICD-10 code for mumps
From the official ICD-10-CM alphabetic index entry “Mumps”. Page updated September 29, 2026.
About coding mumps
The ICD-10-CM code for mumps is B26.9 (Mumps without complication). The official index lists 11 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on B26.9.
Within B26, choose B26.9 (without complication) only when documentation doesn't support a more specific option: orchitis (B26.0), meningitis (B26.1), encephalitis (B26.2), pancreatitis (B26.3) and with other complications (B26.8).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 865 (Viral Illness with MCC, relative weight 1.3485) and DRG 866 (Viral Illness without MCC, relative weight 0.8692), in MDC 18 (Infectious and Parasitic Diseases, Systemic or Unspecified Sites), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific mumps codes (official index)
- arthritis B26.85 — Mumps arthritis
- complication NEC B26.89 — Other mumps complications
- encephalitis B26.2 — Mumps encephalitis
- hepatitis B26.81 — Mumps hepatitis
- meningitis (aseptic) B26.1 — Mumps meningitis
- meningoencephalitis B26.2 — Mumps encephalitis
- myocarditis B26.82 — Mumps myocarditis
- oophoritis B26.89 — Other mumps complications
- orchitis B26.0 — Mumps orchitis
- pancreatitis B26.3 — Mumps pancreatitis
- polyneuropathy B26.84 — Mumps polyneuropathy
Common questions about mumps ICD-10 codes
What is the ICD-10 code for mumps?
- B26.9 — Mumps without complication. More specific codes apply when the documentation supports them: B26.85, B26.89, B26.2, B26.81 and others below.
What is the ICD-10 code for arthritis mumps?
- B26.85 — Mumps arthritis.
What is the ICD-10 code for complication nec mumps?
- B26.89 — Other mumps complications.
What is the ICD-10 code for encephalitis mumps?
- B26.2 — Mumps encephalitis.
What is the ICD-10 code for hepatitis mumps?
- B26.81 — Mumps hepatitis.
What is the ICD-10 code for meningitis mumps?
- B26.1 — Mumps meningitis.
What is the ICD-10 code for meningoencephalitis mumps?
- B26.2 — Mumps encephalitis.
Is B26.9 billable?
- Yes. B26.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can B26.9 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict B26.9 as a principal diagnosis.
Is B26.9 a CC or MCC?
- No. B26.9 is neither a CC nor an MCC under MS-DRG v44.0.