ICD-10-CM 2027
ICD-10 code for chronic tonsillitis
From the official ICD-10-CM alphabetic index entry “Tonsillitis (acute) (catarrhal) (croupous) (follicular) (gangrenous) (infective) (lacunar) (lingual) (malignant) (membranous) (parenchymatous) (phlegmonous) (pseudomembranous) (purulent) (septic) (subacute) (suppurative) (toxic) (ulcerative) (vesicular) (viral) › chronic”. Page updated September 29, 2026.
About coding chronic tonsillitis
The ICD-10-CM code for chronic tonsillitis is J35.01 (Chronic tonsillitis). The official index lists 1 more specific code, so check the documentation for details such as type, cause, site or severity before settling on J35.01.
Within J35.0 (chronic tonsillitis and adenoiditis), J35.01 is specifically for chronic tonsillitis. Related codes cover adenoiditis (J35.02) and tonsillitis and adenoiditis (J35.03).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 011 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with MCC, relative weight 5.6154), DRG 012 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with CC, relative weight 4.381), DRG 013 (Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy without CC/MCC, relative weight 2.7307), DRG 152 (Otitis Media and URI with MCC, relative weight 1.1151) and DRG 153 (Otitis Media and URI without MCC, relative weight 0.7421), in Pre-MDC and MDC 03 (Diseases and Disorders of the Ear, Nose, Mouth and Throat), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific chronic tonsillitis codes (official index)
- with adenoiditis J35.03 — Chronic tonsillitis and adenoiditis
Common questions about chronic tonsillitis ICD-10 codes
What is the ICD-10 code for chronic tonsillitis?
- J35.01 — Chronic tonsillitis. More specific codes apply when the documentation supports them: J35.03.
Is J35.01 billable?
- Yes. J35.01 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can J35.01 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict J35.01 as a principal diagnosis.
Is J35.01 a CC or MCC?
- No. J35.01 is neither a CC nor an MCC under MS-DRG v44.0.