R51.9UpcomingBillable / specific

Headache, unspecified

Excludes 2 · 7

Chapters 18 · Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99)

Excludes 2

abnormal findings on antenatal screening of mother (O28.-)
certain conditions originating in the perinatal period (P04-P96)
signs and symptoms classified in the body system chapters
signs and symptoms of breast (N63, N64.5)

R51 · Headache

Excludes 2

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

Claims & coverage

Coverage depends on the payer, service and applicable policy. A billable code does not guarantee payment.

When ICD-10-CM is required

For US diagnosis claims covered by HIPAA, ICD-10-CM is required from October 1, 2015.

Use the service date for outpatient/professional claims and the discharge date for hospital inpatient claims. Earlier encounters use ICD-9-CM; each individual code must also be valid for the applicable date.

Official coding guidelines → · CMS ↗

Check Medicare coverage ↗

First observed · 2020-10-01

Code history

Latest recorded change · FY2021

ChangedUnchanged

FY2021

Effective from 2020-10-01

Added

Headache, unspecified

Billable diagnosis code

CDC/NCHS · FY2021

All editions (13)

All editions	Effective from	Code history
FY2021	2020-10-01	Added
FY2021 · 01-01	2021-01-01	No tabular change
FY2022	2021-10-01	No tabular change
FY2022 · 04-01	2022-04-01	No tabular change
FY2023	2022-10-01	No tabular change
FY2023 · 04-01	2023-04-01	No tabular change
FY2024	2023-10-01	No tabular change
FY2024 · 04-01	2024-04-01	No tabular change
FY2025	2024-10-01	No tabular change
FY2025 · 04-01	2025-04-01	No tabular change
FY2026	2025-10-01	No tabular change
FY2026 · April	2026-04-01	No tabular change
FY2027	2026-10-01	No tabular change

Code-level instructions

Inclusion terms

Facial pain NOS

Inherited instructions

Chapters 18 · Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99)

Excludes 2

abnormal findings on antenatal screening of mother (O28.-)
certain conditions originating in the perinatal period (P04-P96)
signs and symptoms classified in the body system chapters
signs and symptoms of breast (N63, N64.5)

Note

This chapter includes symptoms, signs, abnormal results of clinical or other investigative procedures, and ill-defined conditions regarding which no diagnosis classifiable elsewhere is recorded.
Signs and symptoms that point rather definitely to a given diagnosis have been assigned to a category in other chapters of the classification. In general, categories in this chapter include the less well-defined conditions and symptoms that, without the necessary study of the case to establish a final diagnosis, point perhaps equally to two or more diseases or to two or more systems of the body. Practically all categories in the chapter could be designated 'not otherwise specified', 'unknown etiology' or 'transient'. The Alphabetical Index should be consulted to determine which symptoms and signs are to be allocated here and which to other chapters. The residual subcategories, numbered .8, are generally provided for other relevant symptoms that cannot be allocated elsewhere in the classification.
The conditions and signs or symptoms included in categories R00-R94 consist of:
(a) cases for which no more specific diagnosis can be made even after all the facts bearing on the case have been investigated;
(b) signs or symptoms existing at the time of initial encounter that proved to be transient and whose causes could not be determined;
(c) provisional diagnosis in a patient who failed to return for further investigation or care;
(d) cases referred elsewhere for investigation or treatment before the diagnosis was made;
(e) cases in which a more precise diagnosis was not available for any other reason;
(f) certain symptoms, for which supplementary information is provided, that represent important problems in medical care in their own right.

R51 · Headache

Excludes 2

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

Official index references (5)

Headache (4)

Pain(s) (1)

Pain(s) › face, facialDisease index

Official conversion history

Historical assignments from the CDC conversion table support data retrieval. They do not authorize substituting a previous code for the current code.

Release dates 2020-10-01

Previous assignment: R51

Related codes

Other entries in the same category; these are not automatic substitutes.

Code	Description	Category · further specificity required
R51.0	Headache with orthostatic component, not elsewhere classified	Billable / specific

Official titles and instructions are preserved in their source language. Official sources ↗

References from other codes (4)

G43 · Migraine

Excludes 2 · headache NOS (R51.9)

G44 · Other headache syndromes

Excludes 1 · headache NOS (R51.9)

G89 · Pain, not elsewhere classified

Excludes 2 · headache (R51.9)

R52 · Pain, unspecified

Excludes 1 · headache (R51.9)

Claims & coverage

Coverage depends on the payer, service and applicable policy. A billable code does not guarantee payment.

When ICD-10-CM is required

For US diagnosis claims covered by HIPAA, ICD-10-CM is required from October 1, 2015.

Official coding guidelines → · CMS ↗

Check Medicare coverage ↗

All editions

Effective from

Code history

FY2021

2020-10-01

Added

FY2021 · 01-01

2021-01-01

No tabular change

FY2022

2021-10-01

No tabular change

FY2022 · 04-01

2022-04-01

No tabular change

FY2023

2022-10-01

No tabular change

FY2023 · 04-01

2023-04-01

No tabular change

FY2024

2023-10-01

No tabular change

FY2024 · 04-01

2024-04-01

No tabular change

FY2025

2024-10-01

No tabular change

FY2025 · 04-01

2025-04-01

No tabular change

FY2026

2025-10-01

No tabular change

FY2026 · April

2026-04-01

No tabular change

FY2027

2026-10-01

No tabular change

Chapters 18 · Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R99)

Excludes 2

abnormal findings on antenatal screening of mother (O28.-)
certain conditions originating in the perinatal period (P04-P96)
signs and symptoms classified in the body system chapters
signs and symptoms of breast (N63, N64.5)

Note

This chapter includes symptoms, signs, abnormal results of clinical or other investigative procedures, and ill-defined conditions regarding which no diagnosis classifiable elsewhere is recorded.
Signs and symptoms that point rather definitely to a given diagnosis have been assigned to a category in other chapters of the classification. In general, categories in this chapter include the less well-defined conditions and symptoms that, without the necessary study of the case to establish a final diagnosis, point perhaps equally to two or more diseases or to two or more systems of the body. Practically all categories in the chapter could be designated 'not otherwise specified', 'unknown etiology' or 'transient'. The Alphabetical Index should be consulted to determine which symptoms and signs are to be allocated here and which to other chapters. The residual subcategories, numbered .8, are generally provided for other relevant symptoms that cannot be allocated elsewhere in the classification.
The conditions and signs or symptoms included in categories R00-R94 consist of:
(a) cases for which no more specific diagnosis can be made even after all the facts bearing on the case have been investigated;
(b) signs or symptoms existing at the time of initial encounter that proved to be transient and whose causes could not be determined;
(c) provisional diagnosis in a patient who failed to return for further investigation or care;
(d) cases referred elsewhere for investigation or treatment before the diagnosis was made;
(e) cases in which a more precise diagnosis was not available for any other reason;
(f) certain symptoms, for which supplementary information is provided, that represent important problems in medical care in their own right.