The purpose of this study is to understand the most influential factors affecting the selection of container shipping lines in Karachi, Pakistan and to assist shipping lines to formulate their strategies and long-term goals by influential factors. Reliability, transport cost, responsiveness and IT orientation and communication are the key influential factors in the selection of container shipping lines. An online survey was conducted to acquire responses from shipping line customers, i.e., freight forwarders, exporters, manufacturers, etc. Questionnaires were sent to 350 individuals who have a clear responsibility of selecting container shipping line based on their preferences and logistics requirement. Out of these 350 respondents, 150 usable responses were received having a response rate of 44%. Data were analyzed by using SPSS Statistics. Multiple regression tests were run to evaluate influential factors on the selection of container shipping lines. The Reliability test was also executed to indicate significance.