Abstract: Coin charging system for mobile telephony in order to facilitate the making of telephone calls by means of a mobile telephone with a coin charging system, mainly in public transport means such as buses, airplanes, trains, ships etc., the system being provided with normal operation modes as rating device, changing of rate device and verification system to visualize the amounts and time units available. The system is comprised of a control subsystem (1), a coin selecting and charging subsystem (2), a display subsystem (3) and a supply subsystem (4).