Is ICD-10-CM code R51 billable?

No, R51 (Headache) is a non-billable ICD-10-CM code. It must be coded to a more specific subcategory before it can be used for reimbursement.

What chapter does ICD-10-CM code R51 belong to?

R51 belongs to Chapter 18 of the ICD-10-CM tabular list: R00–R99 (Symptoms, Signs and Abnormal Clinical and Laboratory Findings).

R51Not billable, use a more specific code below

Headache

In General symptoms and signs (R50-R69), chapter 18: Symptoms, Signs and Abnormal Clinical and Laboratory Findings

2 billable codes under R51: none are a CC or MCC; none map to an HCC.

Instructional notes

Excludes2: not included here, code separately if applicable

atypical face pain (G50.1)
migraine and other headache syndromes (G43-G44)
trigeminal neuralgia (G50.0)

Official coding guidelines

From the ICD-10-CM Official Guidelines for Coding and Reporting, FY 2027 (CMS and NCHS). Links open the PDF at the right page.

Covers when to report symptom, sign, and abnormal finding codes (R00-R99), plus specific rules for falls, coma scales, non-infectious SIRS, death NOS, and NIHSS scores.

Use of symptom codes (page 75)
Use of a symptom code with a definitive diagnosis code (page 75)
Combination codes that include symptoms (page 75)
Repeated falls (page 76)
Coma (page 76)
Functional quadriplegia (page 76)
SIRS due to Non-Infectious Process (page 77)
Death NOS (page 77)

Read Section I.C.18 (page 75), 1 more topics

All codes under R51

R51 can't be used on a claim. Pick a billable code below; grey headings group them.

R51 MS-DRGs

As the principal diagnosis, all 2 billable codes under R51 group to MS-DRG 102 or 103 (v44.0). Which one applies depends on procedures performed, secondary diagnoses (CC/MCC), and the patient's age and discharge status.

About the condition

Plain-language background from MedlinePlus (National Library of Medicine), not coding guidance.

Headache

Almost everyone has had a headache. Headache is the most common form of pain. It's a major reason people miss days at work or school or visit the doctor.

Code history

Valid since FY2016, when ICD-10-CM took effect on October 1, 2015.

FY2021: Subcodes were added, so R51 is no longer billable on its own. New codes for cases coded here before: R51.0 (Headache with orthostatic component, not elsewhere classified), R51.9 (Headache, unspecified).

ICD-9-CM equivalent

Legacy crosswalk from the CMS General Equivalence Mappings (last updated 2018).

784.0 Headache (approximate)

ICD-9 to ICD-10 converter