H70.1 Chronic mastoiditis

⚠ Non-Billable ICD-10-CM 2026
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The ICD-10-CM code for Chronic mastoiditis is H70.1 (FY2026). It is a non-billable category code — select a more specific code below for claims.

Classification

Section
H65-H75: Diseases of middle ear and mastoid (H65-H75)
Category H70
54 codes (40 billable)
FY2026 Status
Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to H70.1:

  • Mastoiditis (coalescent) (hemorrhagic) (suppurative) › chronic (necrotic) (recurrent)
Excludes1
Not coded here. These conditions should NOT be coded together with H70.1.
  • tuberculous mastoiditis (A18.03)

Inclusion Terms

  • Caries of mastoid
  • Fistula of mastoid

Official Coding Guidelines

Chapter 8 reserved for future guideline expansion

8. Chapter 8: Diseases of the Ear and Mastoid Process (H60-H95) Reserved for future guideline expansion

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.8

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

Related Codes

Parent Code

H70 Mastoiditis and related conditions

More Specific Codes

H70.10 Chronic mastoiditis, unspecified ear H70.11 Chronic mastoiditis, right ear H70.12 Chronic mastoiditis, left ear H70.13 Chronic mastoiditis, bilateral

Related Codes in H70

H70 Mastoiditis and related conditions H70.0 Acute mastoiditis H70.00 Acute mastoiditis without complications H70.001 Acute mastoiditis without complications, right ear H70.002 Acute mastoiditis without complications, left ear H70.003 Acute mastoiditis without complications, bilateral H70.009 Acute mastoiditis without complications, unspecified ear H70.01 Subperiosteal abscess of mastoid H70.011 Subperiosteal abscess of mastoid, right ear H70.012 Subperiosteal abscess of mastoid, left ear H70.013 Subperiosteal abscess of mastoid, bilateral H70.019 Subperiosteal abscess of mastoid, unspecified ear H70.09 Acute mastoiditis with other complications H70.091 Acute mastoiditis with other complications, right ear H70.092 Acute mastoiditis with other complications, left ear H70.093 Acute mastoiditis with other complications, bilateral H70.099 Acute mastoiditis with other complications, unspecified ear H70.10 Chronic mastoiditis, unspecified ear H70.11 Chronic mastoiditis, right ear H70.12 Chronic mastoiditis, left ear
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Reviewed by Prajwal Shrestha, CPC, CRC
Certified Professional Coder (CPC) and Certified Risk Adjustment Coder (CRC) · AAPC Member ID 01997614 · About · Editorial policy · Content last reviewed: 2025-10-01

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