Telecommunications plays a major role worldwide with the aim of achieving a bettersocial life for citizens and is one of the major factors contributing to economic growth.This study provides an efficiency analysis of mobile operators in Colombia, Venezuela,Chile and Brazil.For the empirical analysis, the stochastic frontier functions approach is employed toanalyze data from 10 mobile operators from the sample countries. Mobile operators inColombia are compared with others from Venezuela, Chile, and Brazil. Panel data from2005 to 2007 is used in the analysis.The efficiency estimation for each operator over time shows that the level is affectedby some firms and market characteristics such as: type of ownership, market share, typeof technology and firm level wages. One of the main findings of this research is thatsmaller operators work at the same level of efficiency compared with their largercounterparts. ©2010 by Nova Science Publishers, Inc. All rights reserved.