2027 ICD-10-CM Diagnosis Code H70Mastoiditis and related conditions

ICD-10-CM Codes›H60–H95›H65-H75›H70

ICD-10-CM H70
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

H70 is a non-billable ICD-10-CM category code for mastoiditis and related conditions, so it cannot be submitted on claims. Use a more specific code from this category instead, such as H70.001, H70.002, H70.003, and H70.009.

Code Identity

ICD-10-CM Code
H70
Billable Status
No — Non-Billable Category
Code Describes
Mastoiditis and related conditions
Short Description
Mastoiditis and related conditions
Same as the full description in the CMS dataset.
Chapter
H65-H75
Diseases of middle ear and mastoid

Code Classification

ChapterH60–H95Diseases of the ear and mastoid process
SectionH65-H75Diseases of middle ear and mastoid
CategoryH70Mastoiditis and related conditions
This CodeH70Mastoiditis and related conditions

Specific Coding for Mastoiditis and related conditionsOverview

Non-specific codes like H70 require more characters. Use one of these billable codes instead:

  • H70.0 for Acute mastoiditis

  • H70.00 for Acute mastoiditis without complications

  • H70.01 for Subperiosteal abscess of mastoid

  • H70.09 for Acute mastoiditis with other complications

  • H70.1 for Chronic mastoiditis

  • Use H70.10 for Chronic mastoiditis, unspecified ear

  • Use H70.11 for Chronic mastoiditis, right ear

  • Use H70.12 for Chronic mastoiditis, left ear

  • Use H70.13 for Chronic mastoiditis, bilateral

  • H70.2 for Petrositis

  • H70.20 for Unspecified petrositis

  • H70.21 for Acute petrositis

  • H70.22 for Chronic petrositis

  • H70.8 for Other mastoiditis and related conditions

  • H70.81 for Postauricular fistula

  • H70.89 for Other mastoiditis and related conditions

  • H70.9 for Unspecified mastoiditis

  • Use H70.90 for Unspecified mastoiditis, unspecified ear

  • Use H70.91 for Unspecified mastoiditis, right ear

  • Use H70.92 for Unspecified mastoiditis, left ear

  • Use H70.93 for Unspecified mastoiditis, bilateral

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to H70: its own notes plus those printed at Chapter 8. A note printed at a category, block or chapter applies to every code under it.

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 8 (H60-H95) Diseases of the ear and mastoid process applies to 653 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)

Notes

General instructions on how these codes are used.

From Chapter 8 (H60-H95) Diseases of the ear and mastoid process applies to 653 codes
  • Use an external cause code following the code for the ear condition, if applicable, to identify the cause of the ear condition

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name H70, its category, or a range that includes it.

Excludes2 1

These codes carry an Excludes2 note naming H70: its condition is not part of those codes, and both may be reported when the patient has both.

  • H74 Other disorders of middle ear mastoid
    mastoiditis (H70.-)

Patient EducationClinical

Ear Infections

Ear infections are the most common reason parents bring their child to a doctor. Three out of four children will have at least one ear infection by their third birthday. Adults can also get ear infections, but they are less common.

Read the full article at MedlinePlus

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

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 H70Overview

What is the ICD-10 code for mastoiditis and related conditions?

H70 is the ICD-10-CM category for mastoiditis and related conditions, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

Is H70 (Mastoiditis and related conditions) a billable code?

No. This is a category header that groups the codes for mastoiditis and related conditions, and headers cannot be submitted on claims. Claims for mastoiditis and related conditions need a more specific code from this category, such as H70.001, H70.002, and H70.003.