ICD-10 Code G43.9 – Migraine, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G43.9 – Migraine, unspecified
What it is
G43.9 identifies migraine when the record does not specify aura, status migrainosus, or another defined subtype. Use it for a documented migraine diagnosis that lacks further detail.
Clinical signs
Clinical features vary; refer to documentation. Migraine is commonly described as recurrent headache with nausea, photophobia, phonophobia, or activity-related worsening, but the note must support the diagnosis.
When to use this code
Use this code when the provider documents migraine but does not name a more specific type. It is appropriate for outpatient, emergency, or follow-up notes when the chart only states “migraine” or “migraine headaches.”
If the record later specifies migraine with aura or another subtype, you should code that more specific diagnosis instead. Check documentation for laterality, chronicity, and any associated neurologic features.
Do not use for
Do not use G43.9 for tension-type headache, cluster headache, or headache NOS without a migraine diagnosis. Do not use it when the documentation clearly identifies a different migraine subtype.
Coding tip
If the note only says “headache,” query for migraine before assigning G43.9.