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Modifier 77

Definition

Modifier 77 is used when the same procedure is repeated by a different physician on the same patient on the same day. The procedure must be medically necessary, typically because the first attempt was unsuccessful or results were inadequate. Modifier 77 indicates a clinically justified second attempt by an alternative provider.

When to Use

  1. First physician attempts joint injection; fails to locate anatomy; second physician re-injects same joint (20610 first by Dr. A, 20610-77 by Dr. B)
  2. Radiologist reviews initial EKG; requests second reading by cardiologist same day (93000 first, 93000-77 second)
  3. Orthopedic physician attempts reduction of fracture; calls in trauma surgeon for second attempt (27238 first by orthopedist, 27238-77 by trauma surgeon)
  4. Emergency medicine physician attempts procedure; calls in specialist for repeat (92004 comprehensive eye exam first, 92004-77 by ophthalmologist)

Documentation Requirements

Document both physicians' involvement clearly. Show in chart why first attempt by first physician did not succeed and why second physician was called. Note time of first attempt and time of second attempt (typically within hours). Each physician documents separately. First physician notes failure; second physician notes findings and success or reason for second failure.

Payer-Specific Rules

Payer Acceptance Common Denials Notes
Medicare Accepted with clinical documentation CO-117: Service denied as related to global period Allow 77 for failed attempts by different providers. Require chart notes from both.
Aetna Accepted with medical necessity CO-151: Claim documentation insufficient Will pay if both physicians documented. Deny without clear clinical justification.
United Healthcare Accepted; lower scrutiny than 76 CO-4: Service bundled Easier approval than 76 since different provider suggests clinical need.
Cigna Accepted when documented CO-3: Procedure in global period Will review. Pay on appeal if failed first attempt clearly documented.
Humana Accepted with justification CO-116: Frequency exceeds norms Lower deny rate than 76. Payer accepts logic of second opinion/provider.
  • 76 – Repeat by same physician. Use if same physician repeats procedure.
  • XP – Separate practitioner. Use when different practitioner provides service on same day (not necessarily repeat).
  • 91 – Repeat lab test by different lab/technician.

Common Denials

CARC Code Reason Primary Cause
CO-117 Service related to global surgery Modifier 77 applied but procedure falls within global period.
CO-151 Documentation missing Chart lacks clear documentation from first physician of failed attempt.
CO-4 Service bundled Payer contract bundles repeat procedures regardless of modifier.

FAQ

Can I use modifier 77 if both physicians are from the same group?

Yes, as long as they are different individual physicians. Group affiliation does not matter.

What if the second physician performs a different procedure?

Do not use modifier 77. Use the appropriate code for the different procedure.

Do both physicians need to bill, or just the second?

Typically, both physicians bill their separate services with appropriate modifiers and documentation.

Prevent These Denials

Ensure second-attempt claims pay. Use a co-pilot to document failed first attempts properly.

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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