H70.12 – Chronic mastoiditis, left ear
ICD-10-CM 2027 diagnosis code · Diseases of middle ear and mastoid
ICD-10-CM code
H70.12
- Code
H70.12(claims format:H7012)- Description
- Chronic mastoiditis, left ear
- Billable
- Yes – valid for HIPAA-covered transactions
- Valid for
- Dates of service October 1, 2026 – September 30, 2027 (FY2027)
- Chapter
- 8. Diseases of the ear and mastoid process (H60-H95)
- Block
- H65-H75 Diseases of middle ear and mastoid
- Parent codes
- H70 › H70.1
Notes inherited from parent codes
Instructional notes at a category or block level apply to every code below it.
H70.1 – Chronic mastoiditis
Applicable to:
- Caries of mastoid
- Fistula of mastoid
Excludes1 (not coded here):
- tuberculous mastoiditis (A18.03)
Related codes in H70.1
Frequently asked questions
What is ICD-10 code H70.12?
H70.12 is the ICD-10-CM code for chronic mastoiditis, left ear, in the block H65-H75 (Diseases of middle ear and mastoid).
Is H70.12 a billable code?
Yes. H70.12 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.
What category does H70.12 belong to?
It belongs to category H70 – Mastoiditis and related conditions.
Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.