ICD-10 Code J35.8: Other Chronic Diseases of Tonsils and Adenoids – Complete Coding & Billing Guide

ICD-10 code J35.8 is the correct billable diagnosis code for other chronic diseases of tonsils and adenoids — a category that captures a specific set of named tonsillar and adenoid pathologies that do not fit the more precisely defined codes in the J35 family. Understanding when this code applies (and when it does not) is essential for ENT, otolaryngology, and primary care billing teams aiming to avoid claim denials and audit exposure.

What Does ICD-10 Code J35.8 Mean?

J35.8 — Other chronic diseases of tonsils and adenoids is a valid, billable ICD-10-CM code effective for dates of service from October 1, 2015 through the current fiscal year (FY 2026). It belongs to the J35 category (Chronic diseases of tonsils and adenoids) within Chapter 10 of ICD-10-CM (Diseases of the Respiratory System, J00–J99).

This is an “other specified” code — meaning the provider has identified a specific chronic tonsillar or adenoid condition, but that condition is not individually enumerated elsewhere in the J35 subcategory. Unlike J35.9 (unspecified), J35.8 requires the provider to name the diagnosis; the coder selects J35.8 because the named condition maps to this code rather than a more specific one.

Key attributes of this code:

• Billable: Yes — valid for inpatient and outpatient claims
• ICD-10-CM fiscal year validity: FY 2026 (October 1, 2025 – September 30, 2026)
• MS-DRG groupings: 154, 155, 156 (Other ear, nose, mouth and throat diagnoses with/without MCC/CC); also 011–013 when tracheostomy is involved
• ICD-9-CM crosswalk: Approximate mapping only — no exact ICD-9 equivalent exists for this specificity level

What Conditions and Diagnoses Does J35.8 Cover?

J35.8 captures a defined list of specific chronic tonsillar and adenoid pathologies. This is not a catch-all for any tonsil problem — the conditions that map to J35.8 are named in the ICD-10-CM index and tabular list.

Conditions included under J35.8:

• Tonsillolith (tonsil stone / calculus of tonsil) — calcified debris accumulating in tonsillar crypts
• Amygdalolith — calcification within tonsillar tissue (clinical variant of tonsillolith)
• Adenoid vegetations — chronic, abnormal hypertrophic adenoid tissue not classified as simple hypertrophy
• Cicatrix of tonsil and adenoid — chronic scar tissue following repeated infection or prior procedure
• Tonsillar tag — persistent fibrous or epithelial tag of tonsillar tissue
• Ulcer of tonsil — chronic, non-acute tonsillar ulceration
• Retention cyst of tonsil — cystic lesion within tonsillar tissue

What Does J35.8 Specifically Exclude?

J35.8 does not apply to:

• Acute tonsillitis — coded to J03.x regardless of the underlying organism
• Chronic tonsillitis — J35.01 (tonsillitis alone), J35.02 (adenoiditis alone), J35.03 (combined)
• Tonsil/adenoid hypertrophy — J35.1, J35.2, or J35.3 depending on which structures are involved
• Peritonsillar abscess — J36 (always coded separately; never captured by J35.8)
• Post-procedural bleeding — when tonsillar bleeding is post-surgical, use the appropriate postprocedural complication code, not J35.8

When Is J35.8 the Right Code to Use?

J35.8 is appropriate when the provider has documented a named, chronic tonsillar or adenoid condition that maps specifically to this code and cannot be reported with a more precise J35 subcategory. Follow this decision sequence:

1. Confirm the diagnosis is chronic — acute or subacute presentations do not qualify; J35.8 applies only to established, ongoing conditions.
2. Verify the named condition appears in the ICD-10-CM Alphabetic Index under one of the J35.8 entries (e.g., Tonsillolith → J35.8; Cicatrix, tonsil → J35.8).
3. Rule out a more specific code — check whether a more defined J35.x subcategory (J35.01–J35.3) covers the condition before defaulting to J35.8.
4. Confirm it is not unspecified — if the provider has not documented a specific condition (just “chronic tonsil/adenoid disease”), J35.9 is correct, not J35.8.
5. Document chronicity — the clinical note must reflect an ongoing or recurrent condition, not a one-time acute finding.

How Does J35.8 Differ From J35.9?

The most frequently misapplied distinction in the J35 family is between J35.8 and J35.9.

In practice, coders frequently see J35.9 applied when the provider has clearly written “tonsillolith” in the note — a direct map to J35.8. This is a compliance risk that coding audit preparation teams should flag as a pattern.

What Documentation Is Required to Support J35.8?

What Must the Provider Document in the Clinical Notes?

The medical billing documentation requirements for J35.8 hinge on two things: naming the specific condition and establishing chronicity. Required elements include:

1. The specific diagnosis — use accepted clinical terminology (e.g., “tonsillolith,” “tonsillar cicatrix,” “adenoid vegetation”) rather than vague descriptors like “tonsil problem.”
2. Duration or chronicity — a statement that the condition is chronic, longstanding, or recurrent (e.g., “recurrent tonsilloliths over the past 18 months”).
3. Relevant symptoms — chronic halitosis, recurrent throat discomfort, foreign body sensation, or dysphagia as applicable.
4. Physical examination findings — direct visualization findings (e.g., “calcified debris noted in bilateral tonsillar crypts,” “fibrous tag visible at left tonsillar fossa”).
5. Treatment plan — whether observation, procedural intervention, or surgical referral is indicated.

Which Diagnostic or Lab Results Support J35.8?

Not all J35.8 conditions require ancillary studies, but the following may be documented when obtained:

• Imaging (CT or plain film of neck/lateral soft tissue): Particularly useful for tonsillolith confirmation — documents size, location, and calcification characteristics
• Laryngoscopy or nasopharyngoscopy findings: Directly visualized adenoid vegetations or tonsillar pathology
• Culture results: May support chronicity when repeated bacterial colonization is documented
• Pathology report: Relevant when excised tonsillar material (cicatrix, cyst) is sent to pathology

What Is the Documentation Standard for Inpatient vs. Outpatient Settings?

How Does J35.8 Affect Medical Billing and Claims?

J35.8 supports medical necessity for a range of ENT evaluation and management (E/M) visits and, when relevant, surgical procedures. Key billing considerations include:

• This code supports E/M services for chronic disease management in outpatient ENT or primary care settings.
• When tonsillolith removal is performed in-office, no standard CPT code exists for simple manual or instrument-assisted removal — this is a critical billing distinction (see below).
• J35.8 pairs with surgical CPT codes when tonsillectomy or adenoidectomy is performed to treat one of the underlying J35.8 conditions.
• Payers generally do not require prior authorization for the diagnosis code itself, but surgical procedures billed with J35.8 may require prior authorization depending on plan.

What CPT or Procedure Codes Are Commonly Billed With J35.8?

Important billing note on tonsillolith removal: As reported in AAPC coding guidance, in-office removal of a tonsil stone without tonsillectomy has no directly matching CPT code. CPT 42999 (unlisted) linked to J35.8 is the most defensible approach, with a comparison to CPT 42809 (foreign body removal from pharynx) as a benchmark for valuation.

Are There Any Prior Authorization or Coverage Restrictions?

• Most commercial payers follow clinical coverage criteria for tonsillectomy (e.g., AAO-HNSF Paradise criteria for recurrent tonsillitis), which may also apply when J35.8 conditions are the surgical indication.
• Medicare does not have a National Coverage Determination (NCD) specific to tonsil/adenoid procedures; Medicare Administrative Contractor (MAC) Local Coverage Determinations (LCDs) govern medical necessity.
• Tonsillolith removal using CPT 42999 will almost always require a narrative justification letter to the payer prior to or at the time of claim submission.
• Adenoid vegetation procedures in pediatric patients may require polysomnography documentation if obstructive sleep-disordered breathing is also a diagnosis.

What Coding Errors Should You Avoid With J35.8?

In practice, auditors and revenue cycle teams encounter the following J35.8 coding errors most frequently:

1. Using J35.9 instead of J35.8 — when the provider has clearly documented a named condition (tonsillolith, tonsillar tag), defaulting to the unspecified code is an undercoding error that may be flagged on a coding audit.
2. Assigning J35.8 for acute presentations — tonsilloliths discovered incidentally during an acute tonsillitis visit should still carry J35.0x for the acute condition; J35.8 is not appropriate as the primary diagnosis in that context.
3. Billing tonsillolith removal with a tonsillectomy code — unless the tonsil is actually removed, CPT 42825/42826 cannot be reported; doing so constitutes upcoding.
4. Missing additional codes for associated symptoms — halitosis documented as a separately addressed complaint should be captured with R19.6 (Halitosis) as an additional code.
5. Applying J35.8 post-surgically — post-procedural complications are coded from the T81.x or specific postprocedural complication range, not J35.8.

What Do Auditors Look for When Reviewing Claims With J35.8?

• Specificity mismatch — J35.8 billed but clinical note only documents generic “chronic tonsil disease”
• Unsupported CPT pairing — tonsillectomy CPT with J35.8 where op note does not document tonsil removal
• Absence of chronicity documentation — no indication in the note that the condition is longstanding vs. acute
• Duplicate coding — J35.8 billed alongside J35.01 or J35.03 for the same encounter without clinical justification for both

How Does J35.8 Relate to Other ICD-10 Codes?

What Is the Correct Code Sequencing When J35.8 Appears With Other Diagnoses?

Per the ICD-10-CM Official Coding Guidelines (Section IV for outpatient):

1. Sequence J35.8 as the first-listed diagnosis when the visit is solely for management of the chronic tonsillar/adenoid condition.
2. When the patient presents for a surgical procedure (tonsillectomy) to treat the J35.8 condition, sequence the J35.8 diagnosis code as the principal/first-listed diagnosis supporting the procedure.
3. If J35.8 coexists with J35.01 (chronic tonsillitis) and both are addressed at the same encounter, code both — sequence based on which condition drove the visit or procedure.
4. Symptom codes (e.g., R19.6 for halitosis) are coded in addition to J35.8 when the symptom is separately evaluated; do not substitute a symptom code for J35.8.

Real-World Coding Scenario — How J35.8 Is Applied in Practice

Clinical scenario: A 34-year-old male presents to an ENT office with a complaint of persistent bad breath and intermittent foreign body sensation in the throat for approximately two years. On examination, the provider notes “multiple bilateral tonsilloliths in enlarged crypts” and documents “chronic tonsillolith formation with associated halitosis.” The provider counsels the patient on conservative measures and refers for tonsillectomy consideration. No tonsil removal is performed at this visit.

Correct Code Application

• J35.8 — Other chronic diseases of tonsils and adenoids (primary diagnosis; tonsillolith maps directly to J35.8)
• R19.6 — Halitosis (additional code; separately documented and addressed)
• CPT 99214 — Office visit, established patient, moderate complexity (E/M only; no procedure performed)

Common Mistake in This Scenario

• Incorrect code: J35.9 (Chronic disease of tonsils and adenoids, unspecified)
  • Why it fails: The provider explicitly documented “tonsilloliths” — a specific, index-listed condition that maps to J35.8. Assigning J35.9 is undercoding and does not reflect the documented diagnosis code specificity required by payer and compliance standards.
• Second common error: Billing CPT 42826 (tonsillectomy) because “tonsillectomy was discussed”
  • Why it fails: The tonsils were not removed at this encounter. A procedure must be performed, not merely planned, to support a surgical CPT code.

Frequently Asked Questions About ICD-10 Code J35.8

Is ICD-10 Code J35.8 Valid for Use in 2026?

ICD-10 code J35.8 remains a valid, billable diagnosis code for fiscal year 2026 with no changes to its description or validity status since its introduction on October 1, 2015. Coders should verify annually against the ICD-10-CM Official Coding Guidelines published by CMS to confirm no revisions have been applied in subsequent fiscal year updates.

What Is the Difference Between J35.8 and J35.9?

J35.8 is the correct code when the provider has documented a specific, named chronic tonsillar or adenoid condition — such as tonsillolith, tonsillar tag, or adenoid vegetations — that maps to this code in the ICD-10-CM index. J35.9 is reserved for encounters where the provider documents only a generic chronic tonsil or adenoid condition without naming a specific pathology. Using J35.9 when J35.8 is supported constitutes an undercoding error.

What Is the ICD-10 Code for a Tonsil Stone (Tonsillolith)?

The correct ICD-10-CM code for a tonsil stone (tonsillolith) is J35.8 — Other chronic diseases of tonsils and adenoids. The ICD-10-CM Alphabetic Index maps “Tonsillolith” directly to J35.8, and the code description covers this condition as a named chronic tonsillar pathology.

What CPT Code Should Be Used for In-Office Tonsil Stone Removal?

There is no standard CPT code that directly describes in-office manual removal of a tonsillolith. Per AAPC coding guidance, the most appropriate approach is to report CPT 42999 (Unlisted procedure, pharynx, adenoids, or tonsils) paired with J35.8, with a supporting narrative letter to the payer comparing the service to CPT 42809 (Removal of foreign body from pharynx) for valuation purposes.

Can J35.8 and J35.01 Be Coded Together?

Yes, J35.8 and J35.01 (Chronic tonsillitis) can be coded together when both conditions are documented and separately addressed at the same encounter. For example, a patient with both tonsilloliths (J35.8) and chronic tonsillitis (J35.01) confirmed in the clinical note may have both codes assigned. Sequence based on the condition chiefly responsible for the visit.

Does J35.8 Require Documentation of Chronicity?

Yes, J35.8 specifically belongs to the J35 category (Chronic diseases of tonsils and adenoids), so the clinical documentation must reflect that the condition is chronic, recurrent, or longstanding. A single acute episode of tonsillolith discovery during an acute illness encounter would not typically support J35.8 as the primary diagnosis; however, if the tonsillolith itself is noted to be a chronic finding, J35.8 is appropriate.

Is J35.8 Covered by Medicare for Tonsillectomy Procedures?

Medicare does not have a specific National Coverage Determination (NCD) for tonsil or adenoid procedures. Coverage for tonsillectomy billed with J35.8 is governed by the applicable MAC’s Local Coverage Determination (LCD) for the region. Providers should confirm that the documented clinical indications (e.g., recurrent tonsillolith formation, functional impairment) meet the LCD’s medical necessity criteria before submitting surgical claims.

Key Takeaways

• J35.8 is the correct code for named, chronic tonsillar and adenoid conditions including tonsillolith, adenoid vegetations, cicatrix of tonsil, tonsillar tag, and ulcer of tonsil.
• J35.8 vs. J35.9 is one of the most common coding errors in this category — use J35.8 only when the provider names a specific condition that maps to it.
• Chronicity must be documented — J35.8 belongs to the chronic disease category and requires clinical evidence of an ongoing or recurrent condition.
• No standard CPT code exists for in-office tonsillolith removal — CPT 42999 (unlisted) with a payer justification letter is the correct approach.
• Tonsillectomy CPT codes require that the tonsil is actually removed — discussion or referral alone does not support billing 42825 or 42826.
• Halitosis (R19.6) should be coded additionally when it is separately documented and managed alongside a J35.8 diagnosis.
• For revenue cycle compliance and coding audit preparation, ensure provider education targets J35.8 vs. J35.9 specificity and the unlisted code pathway for tonsil stone removal.

For additional guidance on chronic respiratory diagnosis coding, refer to the ICD-10-CM Official Coding Guidelines published annually by CMS at cms.gov, and consult AHA Coding Clinic for official guidance on specific scenarios.