R51.9Billable
Headache, unspecified
- Chapter
- 18. Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
- Category
- R51
- Effective date
- October 1, 2026
Related codes in category R51
Frequently asked questions
What is ICD-10 code R51.9?
R51.9 is an ICD-10-CM diagnosis code for Headache, unspecified.
Is R51.9 a billable code?
Yes. R51.9 is billable and specific enough to be used on a claim.
What ICD-10-CM chapter is R51.9 in?
R51.9 falls under Chapter 18: Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified.
When did R51.9 become effective?
R51.9 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.
What other codes are related to R51.9?
R51.9 belongs to category R51, which includes 2 other codes — see the related codes list on this page.
ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.