A system, mobile fax terminal, and method for providing fax service for mobile networks. A fax adapter receives fax data from a fax machine via standard fax protocols, maps the fax data onto Transmission Control Protocol (TCP) or User Datagram Protocol (UDP) packets, and sends the mapped data over an Internet Protocol (IP)-based interface to a mobile phone portion. The mobile phone portion maps the TCP or UDP packets onto Radio Link Protocol (RLP) frames, and transmits the RLP frames to an external radio telecommunication network.