Systems and methods are provided to facilitate on-site processing of transaction requests. In one aspect, a system includes a data storage facility to store an account identifier of a user and a phone number of the user and an interchange coupled with the data storage facility. The interchange includes a common format processor and a plurality of converters to interface with a plurality of different controllers of mobile communications. The converters are configured to communicate with the controllers in different formats and to communicate with the common format processor in a common format to transmit a message to a telephone at the telephone number of the user to prompt the user to confirm a request and to receive a confirmation of the request via the telephone. The request is received via a user interface embedded in a web page of a first website without reloading or refreshing the web page.