RMA stands for "return merchandise authorization" and is a part of the process of returning a product to receive a refund, replacement, or repair to which buyer and seller agree during the products warranty. An RMA is a numbered authorization provided by a mail-order or e-commerce merchant to permit the return of a product. The issuance of an RMA is a key gatekeeping moment in the reverse logistics cycle, providing the vendor with a final opportunity to diagnose and correct the customers problem with the product before the customer permanently relinquishes ownership of the product to the manufacturer. The RMA number is generally assigned by the customer service department when the return is being processed, and the return authorization form will list the policies regarding the return, as well as any special instructions on how to package and ship the product back to the retailer. RMAs may be minimized in a number of ways, such as adding a customer survey capability to prevent RMAs by detecting problems in advance of returns.

It is important to note that RMA can also stand for "registered medical assistant," which is a healthcare professional responsible for administrative tasks and basic patient care, such as conducting basic tests, sterilizing instruments, and measuring vital signs.