Modifier 66: Surgical Team Procedure

Definition

Modifier 66 is used to indicate that a procedure required a surgical team of more than two surgeons. The complexity of the procedure necessitates three or more surgeons working together. Each team member typically bills the procedure code with modifier 66, and reimbursement is reduced proportionally (each surgeon receives less than with modifier 62 for two surgeons). Modifier 66 is used for extraordinarily complex procedures.

When to Use

Organ transplant (kidney, liver, heart) requiring transplant surgeon, vascular surgeon, and anesthesiologist-surgeon team
Complex cardiac reconstruction requiring cardiac surgeon, vascular surgeon, and specialized anesthesia surgeon
Separation of conjoined twins requiring multiple surgical specialists working together
Massive trauma with combined vascular, orthopedic, and general surgical repair requiring team approach

Documentation Requirements

Operative report should clearly show three or more surgeons present and working on the procedure. Document each surgeon's role and contribution. Explain why three or more surgeons were necessary due to procedure complexity. All team members should be listed on operative report. Each surgeon may submit separate documentation indicating team membership and role.

Payer-Specific Rules

Payer	Acceptance	Common Denials	Notes
Medicare	Accepted; reduced per-surgeon	CO-20: Charge exceeds fee schedule	Reimburse each surgeon at reduced rate. Typically 25-30% per surgeon for team of 4+. Require documentation.
Aetna	Accepted with documentation	CO-4: Service bundled	Will pay reduced team amount. Require operative report showing all surgeons.
United Healthcare	Accepted; team reduction	CO-66: Surgical team required	Pay reduced per-surgeon amount. Verify surgical team was necessary.
Cigna	Accepted with justification	CO-151: Documentation missing	Will pay. Require evidence three+ surgeons were needed.
Humana	Accepted; standard team reduction	CO-66: Team payment applied	Routine approval. Pay reduced per-surgeon amount.

Related Modifiers

62 – Two surgeons (co-surgeon). Use when only two surgeons; each gets 62.5%.
80 – Assistant surgeon. Use if surgeon is assisting primary surgeon (not team member).

Common Denials

CARC Code	Reason	Primary Cause
CO-20	Charge exceeds fee schedule	Billed full code charge; must bill with team reduction percentage.
CO-66	Surgical team not necessary	Payer deems three surgeons not required for this procedure.
CO-4	Service bundled	Payer contract does not recognize surgical team as override.

FAQ

How many surgeons are needed for modifier 66?

Three or more surgeons. Use modifier 62 for two surgeons; 66 for three or more.

How much reimbursement does each surgeon get with modifier 66?

Varies by team size and payer. Typically 20-35% of code value per surgeon for larger teams.

Can I use modifier 66 for any complex procedure?

No. Modifier 66 requires proof that three or more surgeons were working simultaneously. Simple procedures with available surgeons do not justify 66.

Prevent These Denials

Optimize surgical team claims. Use a co-pilot to document multi-surgeon complexity.

Related Resources

This reference is current as of 2026-03-23. Payer policies change. Always verify against the payer's latest policy documentation.

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