Modifier 50 Fact Sheet

• Modifier 50 applies to bilateral procedures performed on both sides of the body during the same operative session.
• When a procedure is identified by the terminology as bilateral or unilateral, the 50 modifiers are not reported.
• If a procedure is authorized for the 150 percent payment adjustment for bilateral procedures (payment policy indicator 1), the procedure should be reported on a single line item with the 50 modifiers and one service unit.
• Whenever the 50 modifiers are appended, the appropriate number of service units is one.
• Modifiers LT (left side) and RT (right side) are not to be reported when the 50 modifier applies.
• Claims with the LT and RT modifiers will be returned to the provider (RTP) when modifier 50 applies

Effective for claims received on and after August 16, 2019, services will be rejected as un-processable when the procedure code reported is inconsistent with the modifier used. The modifier 50 is defined as a bilateral procedure performed on both sides of the body.

Appropriate Use

• Report one line with modifier 50 using one unit of service
• If more than one bilateral procedure was performed the number of units should be adjusted to reflect the number of bilateral procedures that are performed.

Note: It is recommended that anatomical modifier be included in addition to the 50 modifiers to show the additional services are not duplicates.

Example:

Procedure code 19303 (Mastectomy, simple, complete) is performed bilaterally

Correct Coding

Date of Service	Procedure Code	Modifier	Units
7/1/2019	19303	50	1

Incorrect Coding

Date of Service	Procedure Code	Modifier	Units
7/1/2019	19303	LT	1
7/1/2019	19303	RT	1

Inappropriate Use

• Inappropriate to apply to a “bilateral description” code.
• Do not append to procedures for midline organs such as the bladder, uterus, esophagus, or nasal septum.
• Inappropriate to report when performed on different areas of the same side of the body.
• It cannot be appended when bilateral indicators are 0, 2, or 9.

Example:

The terminology for procedure code 27158 (osteotomy, pelvis, bilateral) indicates the procedure is performed bilaterally. Therefore, it’s not appropriate to report with this procedure code.

Bilateral Surgery Indicators

• “0″ indicates a unilateral code; not billable.
• “1” indicates It can be appropriate.
• “2” indicates a bilateral code; It is not billable.
• “3” indicates primary radiology codes; It is billable.
• “9” indicates that the concept does not apply. (office visit)

Medically Unlikely Edits (MUE) and Bilateral Procedures

When reporting bilateral surgical procedures that have an MUE Adjudication Indicator (MAI) of “2” or “3”, the bill with modifier 50 and one unit of service.

Ambulatory Surgical Centers (ASCs) and Modifier

Bilateral surgical procedures furnished by certified ASCs may be covered under Part B. While the use of the 50 modifiers is not prohibited, according to Medicare billing instructions, the modifier is not recognized for payment purposes and if used, may result in incorrect payment to ASCs.

Bilateral procedures should be reported as a single unit on two separate lines or a single unit with “2” in the unit field on one line, in order for both procedures to be paid correctly. The multiple procedure reduction of 50 percent will apply to all bilateral procedures subject to multiple procedures discounting. Multiple surgery pricing applies to bilateral services (modifier 50) performed on the same day with other procedures.