RETIRED - Correct Use Of RT And LT Modifiers


Content Provided on this page contains outdated information and instruction and should not be considered current. Noridian is providing this archived information for research purposes only. This archived article contains previously issued instructions that have since been updated or are no longer applicable for Medicare billing purposes.

Certain local medical review policies (LMRPs) require the use of RT (right side) and LT (left side) modifiers. Correct use of these modifiers is important to assure that suppliers are paid correctly. Generally, when an item is provided for one side and a like item is not provided for the other side on the same date, the appropriate modifier, LT or RT, should be used. When the same item (code) is provided for both sides on the same date, the combined modifiers, LTRT, must be used on the same line of the claim form with two units of service. Individual exceptions to this coding guideline (e.g., Therapeutic Shoes for Diabetics) may be noted in the Coding Guidelines sections of individual LMRPs.

Suppliers are reminded that when an LMRP specifies the use of these modifiers, they must be used or the claim line(s) will be rejected if the claim is assigned or denied for incorrect coding if the claim is unassigned. Assigned claims must be corrected and resubmitted. Unassigned claims may also be corrected and resubmitted. The following LMRPs currently require the use of the LT/RT modifier:

  • Ankle-Foot/Knee-Ankle-Foot Orthosis
  • External Breast Prosthesis
  • Facial Prostheses
  • Lower Limb Prostheses
  • Orthopedic Footwear
  • Refractive Lenses
  • Therapeutic Shoes for Diabetics
  • Wheelchair Options/Accessories

Past payment for incorrectly billed codes is not an assurance that future claims will be paid when not coded correctly. Edits for correct coding of breast prostheses were implemented with the April 1, 2002 effective date of the revised LMRP. Additional claim edits for other LMRPs will be implemented for claims received on or after September 1, 2002. In the meantime, if you bill for any of these items, you should take steps to assure that your billing software and/or billers are prepared to handle this requirement.

See also the April 1998 Region D DMERC Dialogue, page 6, article entitled "RT/LT Modifiers Requirement."

Revision History

Date of Change Description
09/01/02 Originally Published
03/01/19 Retired


Last Updated Dec 11 , 2023