2027 ICD-10-CM Diagnosis Code S04Injury of cranial nerve

ICD-10-CM Codes›S00–T88›S00-S09›S04

ICD-10-CM S04
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

S04 is a non-billable ICD-10-CM category code for injury of cranial nerve, so it cannot be submitted on claims. Use a more specific code from this category instead, such as S04.011A, S04.011D, S04.011S, and S04.012A.

Code Identity

ICD-10-CM Code
S04
Billable Status
No — Non-Billable Category
Code Describes
Injury of cranial nerve
Short Description
Injury of cranial nerve
Same as the full description in the CMS dataset.
Chapter
S00-S09
Injuries to the head

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionS00-S09Injuries to the head
CategoryS04Injury of cranial nerve
This CodeS04Injury of cranial nerve

Specific Coding for Injury of cranial nerveOverview

Non-specific codes like S04 require more characters. Use one of these billable codes instead:

  • S04.0 for Injury of optic nerve and pathways

  • S04.01 for Injury of optic nerve

  • S04.02 for Injury of optic chiasm

  • S04.03 for Injury of optic tract and pathways

  • S04.04 for Injury of visual cortex

  • S04.1 for Injury of oculomotor nerve

  • S04.10 for Injury of oculomotor nerve, unspecified side

  • S04.11 for Injury of oculomotor nerve, right side

  • S04.12 for Injury of oculomotor nerve, left side

  • S04.2 for Injury of trochlear nerve

  • S04.20 for Injury of trochlear nerve, unspecified side

  • S04.21 for Injury of trochlear nerve, right side

  • S04.22 for Injury of trochlear nerve, left side

  • S04.3 for Injury of trigeminal nerve

  • S04.30 for Injury of trigeminal nerve, unspecified side

  • S04.31 for Injury of trigeminal nerve, right side

  • S04.32 for Injury of trigeminal nerve, left side

  • S04.4 for Injury of abducent nerve

  • S04.40 for Injury of abducent nerve, unspecified side

  • S04.41 for Injury of abducent nerve, right side

  • S04.42 for Injury of abducent nerve, left side

  • S04.5 for Injury of facial nerve

  • S04.50 for Injury of facial nerve, unspecified side

  • S04.51 for Injury of facial nerve, right side

  • S04.52 for Injury of facial nerve, left side

  • S04.6 for Injury of acoustic nerve

  • S04.60 for Injury of acoustic nerve, unspecified side

  • S04.61 for Injury of acoustic nerve, right side

  • S04.62 for Injury of acoustic nerve, left side

  • S04.7 for Injury of accessory nerve

  • S04.70 for Injury of accessory nerve, unspecified side

  • S04.71 for Injury of accessory nerve, right side

  • S04.72 for Injury of accessory nerve, left side

  • S04.8 for Injury of other cranial nerves

  • S04.81 for Injury of olfactory [1st ] nerve

  • S04.89 for Injury of other cranial nerves

  • S04.9 for Injury of unspecified cranial nerve

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Injury of cranial nerve (S04). Use the following options for the applicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2027, published by CMS and the National Center for Health Statistics.

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to S04: its own notes plus those printed at block S00-S09 and Chapter 19. 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 Block S00-S09 Injuries to the head applies to 1,934 codes
  • injuries of ear
  • injuries of eye
  • injuries of face [any part]
  • injuries of gum
  • injuries of jaw
  • injuries of oral cavity
  • injuries of palate
  • injuries of periocular area
  • injuries of scalp
  • injuries of temporomandibular joint area
  • injuries of tongue
  • injuries of tooth

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.

  • The selection of side should be based on the side of the body being affected

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 Block S00-S09 Injuries to the head applies to 1,934 codes
  • burns and corrosions (T20-T32)
  • effects of foreign body in ear (T16)
  • effects of foreign body in larynx (T17.3)
  • effects of foreign body in mouth NOS (T18.0)
  • effects of foreign body in nose (T17.0-T17.1)
  • effects of foreign body in pharynx (T17.2)
  • effects of foreign body on external eye (T15.-)
  • frostbite (T33-T34)
  • insect bite or sting, venomous (T63.4)
From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes

Code First

The underlying condition named in the note is sequenced before this code.

  • any associated intracranial injury (S06.-)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes
  • code to identify any retained foreign body, if applicable (Z18.-)

Code Also

A second code may be needed to fully describe the condition; the note gives no sequencing direction.

On S04 itself
  • any associated:
  • open wound of head (S01.-)
  • skull fracture (S02.-)
From Block S00-S09 Injuries to the head applies to 1,934 codes
  • for any associated infection

Notes

General instructions on how these codes are used.

From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes
  • Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
  • The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.

7th Character

Every code in the category takes a 7th character from the listed values, with the placeholder X filling any empty positions before it.

  • The appropriate 7th character is to be added to each code from category S04
Values for category S04 Encounter: Initial, Subsequent, Sequela
  • Ainitial encounter
  • Dsubsequent encounter
  • Ssequela

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name S04, its category, or a range that includes it.

Code Also 1

These codes say S04 may also be needed to fully describe the condition. The note gives no sequencing direction.

  • S01 Open wound of head
    injury of cranial nerve (S04.-)

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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 S04Overview

What is the ICD-10 code for injury of cranial nerve?

S04 is the ICD-10-CM category for injury of cranial nerve, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

Is S04 (Injury of cranial nerve) a billable code?

No. This is a category header that groups the codes for injury of cranial nerve, and headers cannot be submitted on claims. Claims for injury of cranial nerve need a more specific code from this category, such as S04.011A, S04.011D, and S04.011S.

What is coded first with S04?

The Code First note reads: any associated intracranial injury (S06.-). When one of these applies, it is sequenced before S04.