ICD-10-CM 2027 diagnosis code
J03Acute tonsillitis
J03 is a header code, so it can't be reported by itself. Choose one of the 3 more specific codes beneath it.
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About J03
J03 is the ICD-10-CM diagnosis code for acute tonsillitis. It belongs to block J00-J06 (acute upper respiratory infections) and chapter 10 (diseases of the respiratory system). It is a header code, so it can't be reported by itself; one of its 3 subcodes must be used instead.
To report this condition, pick the subcode that matches the documentation: J03.0 (tonsillitis), J03.8 (due to other specified organisms) and J03.9 (unspecified).
Don't report J03 together with the conditions in its Excludes1 note: acute sore throat (J02.-), hypertrophy of tonsils (J35.1), peritonsillar abscess (J36), sore throat NOS (J02.9) and 1 more.
The conditions in its Excludes2 note aren't part of J03, but may be coded alongside it if the patient has both: chronic tonsillitis (J35.0).
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Specific codes under J03
Coding notes
- chronic tonsillitis (J35.0)
Notes that apply from higher levels
Instructions written at a parent level also apply to J03.
Broader instructions also apply from J00-J06 Acute upper respiratory infections and Chapter 10: Diseases of the respiratory system.
Codes whose notes reference J03
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about J03
Is J03 billable?
- No. J03 is a header code. Report one of its more specific subcodes instead.