Locum tenens, or substitute, physicians usually assume professional practices in the absence of a regular physician for reasons such as illness, pregnancy, vacation, or continuing medical education. The substitute physicians generally have no practice of their own and move from area to area as needed. Medicare rules require that a locum tenens cannot provide services for longer than 60 days (see this exception [ PDF ] for physicians in the armed services; scroll to page 36). The regular physician generally pays the locum tenens a fixed-rate, per diem amount, with the locum tenens having the status of an independent contractor rather than an employee.
The regular physician may submit the claim using the Q6 modifier (services furnished by a locum tenens physician). Additionally, the regular physician must keep on file a record of each service provided by the locum tenens along with the locum tenens' National Provider Identifier. Find all the details in the Medicare Locum Tenens/Reciprocal Billing ( PDF ) manual.
Under reciprocal billing arrangements, a patient's regular physician may submit a claim and receive payment for the services arranged to be provided by a substitute physician on an occasional basis. The regular physician should identify the service as substitute physician services and bill with the Q5 modifier (service furnished by a substitute physician under a reciprocal billing arrangement).
For commercial payers, the requirements may vary, making it necessary to determine billing procedures on a payer-by-payer basis
