S-Fone was a mobile communication operator in Vietnam that used the CDMA technology. Founded on 1 July 2003 in Ho Chi Minh City, Vietnam, S-Fone became the third network of Vietnam, breaking the duopoly of the two VNPT operators. It is the trademark of S-Telecom (CDMA Mobile Phone Centre) (set up as a joint venture between Saigon Postel Corp. (SPT) and Korea SK Telecom). SK Telecom decided to leave the partnership in 2010.[1] SPT has since then found it difficult to find a new partner, after a co-operation with Saigon Tel failed.[1]
As of the start of 2005, breaking the old rule of the calls fee from 10 second to 1 second (6+1)7, S-Fone has 1,500,000 to 1,800,000 subscribers, contributing 3% to the total market (after Mobifone with 41%, Viettel Mobile with 34% and Vinaphone with 20%.[2] Its market share (estimated based on revenues) fell to 0.1% by 2012 after suffering from a lack of capital, a small number of subscribers and low network quality.[3]