2027 ICD-10-CM Diagnosis Code G51.0Bell's palsy

ICD-10-CM Codes›G00–G99›G50-G59›G51

ICD-10-CM G51.0
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

G51.0 is a billable ICD-10-CM diagnosis code for Bell's palsy. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 73 through 74. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nerve and nerve root disorders.

Code Identity

ICD-10-CM Code
G51.0
Billable Status
Yes — Valid for Submission
Code Describes
Bell's palsy
Short Description
Bell's palsy
Same as the full description in the CMS dataset.
Parent Code
G51
Facial nerve disorders

Code Classification

ChapterG00–G99Diseases of the nervous system
SectionG50-G59Nerve, nerve root and plexus disorders
CategoryG51Facial nerve disorders
This CodeG51.0Bell's palsy

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute mastoiditis
  • Acute mastoiditis with facial paralysis
  • Autoimmune movement disorder
  • Bell's palsy
  • Bells palsy of left side of face
  • Bells palsy of right side of face
  • Congenital disorder of facial nerve
  • Congenital facial nerve palsy
  • Congenital hereditary facial paralysis with variable hearing loss syndrome
  • Disorder of left facial nerve
  • Disorder of right facial nerve
  • Facial diplegia with paresthesia
  • Facial nerve motor disorder
  • Facial palsy
  • Facial palsy House-Brackmann grade I
  • Facial palsy House-Brackmann grade II
  • Facial palsy House-Brackmann grade III
  • Facial palsy House-Brackmann grade IV
  • Facial palsy House-Brackmann grade V
  • Facial palsy House-Brackmann grade VI
  • Familial facial nerve palsy
  • Familial recurrent peripheral facial palsy
  • Guillain-Barré syndrome
  • Left facial palsy House-Brackmann grade I
  • Left facial palsy House-Brackmann grade II
  • Left facial palsy House-Brackmann grade III
  • Left facial palsy House-Brackmann grade IV
  • Left facial palsy House-Brackmann grade V
  • Left facial palsy House-Brackmann grade VI
  • Nuclear facial nerve paralysis
  • Peripheral facial palsy
  • Right facial palsy House-Brackmann grade I
  • Right facial palsy House-Brackmann grade II
  • Right facial palsy House-Brackmann grade III
  • Right facial palsy House-Brackmann grade IV
  • Right facial palsy House-Brackmann grade V
  • Right facial palsy House-Brackmann grade VI
  • Sellars Beighton syndrome
  • Supranuclear facial nerve paralysis
  • Supranuclear paralysis

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to G51.0: its own notes plus those printed at G51, block G50-G59, and Chapter 6. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From G51 Facial nerve disorders applies to 10 codes
  • disorders of 7th cranial nerve

Applicable To

Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.

  • Facial palsy

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From Block G50-G59 Nerve, nerve root and plexus disorders applies to 106 codes
  • current traumatic nerve, nerve root and plexus disorders - see Injury, nerve by body region
  • neuralgia NOS (M79.2)
  • neuritis NOS (M79.2)
  • peripheral neuritis in pregnancy (O26.82-)
  • radiculitis NOS (M54.1-)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 6 (G00-G99) Diseases of the nervous system applies to 700 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name G51.0, its category, or a range that includes it.

Excludes1 1

These codes carry an Excludes1 note naming G51.0: they are not reported together with it, unless the two conditions are unrelated.

  • R29.810 Facial weakness
    Bell's palsy (G51.0)

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NVS017
Nerve and nerve root disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Bell Palsy

    a syndrome characterized by the acute onset of unilateral facial paralysis which progresses over a 2-5 day period. weakness of the orbicularis oculi muscle and resulting incomplete eye closure may be associated with corneal injury. pain behind the ear often precedes the onset of paralysis. this condition may be associated with herpesvirus 1, human infection of the facial nerve. (adams et al., principles of neurology, 6th ed, p1376)

Patient EducationClinical

Bell's Palsy

Bell's palsy is the most common cause of facial paralysis. It usually affects just one side of the face. Symptoms appear suddenly and are at their worst about 48 hours after they start. They can range from mild to severe and include:

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert G51.0 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
351.0 Bell's palsy
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About G51.0Overview

What is the ICD-10 code for Bell's palsy?

The ICD-10-CM code for Bell's palsy is G51.0 (sometimes written as G510). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is G51.0 (Facial nerve disorders) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report Bell's palsy on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does G51.0 group to?

When Bell's palsy is the principal diagnosis on an inpatient stay, it groups to MS-DRG 74, 73, with relative weights from 1.0172 to 1.5773 depending on complications. Higher weights mean higher Medicare reimbursement.

Can G51.0 be reported with M79.2?

Not as a rule. The Excludes1 note at block G50-G59, which applies to G51.0, lists "neuralgia NOS (M79.2)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

What is the ICD-9 equivalent of G51.0?

Under the General Equivalence Mappings, Bell's palsy converts to ICD-9-CM 351.0 (Bell's palsy). The mapping is a direct match.