CPT code 42821: Tonsil and adenoid removal, age 12 or older2026 Medicare rate & RVUs in California

CMS doesn’t publish an office rate for 42821 in California.

Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.

What 42821 covers

An otolaryngologist removes the palatine tonsils and adenoid tissue during the same operation. Common clinical settings include surgery for recurrent tonsillitis or adenotonsillar enlargement associated with obstructive sleep-disordered breathing. The code applies when the patient is 12 or older and both sites are treated; tonsil removal alone or adenoid removal alone calls for a different code. These procedures are typically performed in a facility operating room.

The operative report should identify the patient’s age and document removal of both the tonsils and adenoids, along with the clinical reason. The combined procedure is reported as one service rather than as separate tonsil and adenoid procedures. It has a 90-day global period, including the day-before preoperative visit and related postoperative care. For other procedures performed in the same session, the highest-valued procedure is paid in full and additional procedures are subject to the standard 50% multiple-procedure reduction. Modifier 50 is inappropriate. Assistant-at-surgery payment requires documented medical necessity; co-surgeon and team-surgery billing are not permitted.

This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.

Where 42821 pays more and less in California

The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.

29 of 29 payment localities

How the 42821 rate is calculated

Each of 42821’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.

Payment rules and modifiers for 42821

42821 has a 90-day global period: related visits in that window are included in the surgery payment.

What modifiers do to the payment

When to use modifier 51

42821 compared with similar codes

How to choose

42820Tonsil and adenoid removalPatient younger than 12

Use 42820 for combined tonsil and adenoid removal in a patient younger than 12; 42821 is for age 12 or older.

42826TonsillectomyAge 12 or older

42826 covers tonsil removal alone in a patient age 12 or older. Use 42821 when adenoid tissue is also removed.

42831AdenoidectomyPrimary, age 12 or older

42831 covers primary adenoid removal alone in a patient age 12 or older. Use 42821 when the tonsils are removed during the same operation.

Codes related to 42821

Related codes aren’t interchangeable: bill the code that matches the service performed.

Where these rates come from

FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.

CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027

Open CMS sourceHow we calculate rates