R51.9 — Headache, unspecified
R51.9 is a billable, specific ICD-10-CM code for headache, unspecified. It is valid for submission on a claim.
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Facial pain NOS
Other codes that can never be billed with R51.9
These codes carry an Excludes1 note pointing at R51.9. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading R51.9 alone.
Risk adjustment
R51.9 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.
Medicare coverage
R51.9 is named in 6 Medicare coverage policies — 5 listing it as supporting medical necessity, and 1 listing it as NOT covered. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A57497Billing and Coding: Chest X-Ray Policynot covered
- A56273Billing and Coding: Chiropractic Services
- A56612Billing and Coding: CT of the Head
- A57204Billing and Coding: MRI and CT Scans of the Head and Neck
How R51.9 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to R51.9.
- Headache
- Headache›chronic daily
- Headache›daily chronic
- Headache›nasal septum
- Pain›face, facial
Related codes at this level
Codes that share R51. If R51.9 is not quite right, the correct code is usually one of these.
Questions about R51.9
- Is R51.9 a billable ICD-10-CM code?
- Yes. R51.9 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does R51.9 sit in the tabular list?
- Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99), in the block General symptoms and signs (R50-R69).