What is a Medicare modifier?


Editorial team Published on

Medicare modifiers are two-character codes added to medical procedure codes to give extra details about a service without changing its main definition.

What They Do

  • Add Context: They explain special situations, such as which side of the body a procedure used or if a service took extra time.
  • Affect Payment: They help Medicare decide the correct reimbursement amount for a claim.
  • Prevent Denials: They ensure proper processing by clarifying why certain overlapping or bundled services were necessary.

Types of Modifiers

  • Pricing (Reimbursement) Modifiers: These directly change or affect how much money the provider is paid. They usually go first on the billing form.
  • Informational (Statistical) Modifiers: These provide extra facts or tracking data without altering the payment amount. They usually go after pricing modifiers.

Common Examples

  • Modifier 25: Used for a significant, separate evaluation and management (office visit) service done on the same day as another procedure.
  • Modifier 59: Used to show that a procedure is distinct and independent from other services performed on the same day.
  • Modifier RT / LT: Specifies whether a procedure was done on the right side (RT) or left side (LT) of the body.
  • Modifier GA: Used when a required Advance Beneficiary Notice (ABN) is signed because a service might not be covered by Medicare.