Psychological factors and social relationships are important components that influence an individual s communication style. This paper aims to examine the association of personality factors, social anxiety (SA) and loneliness with mobile phone (MP) usage preferences on the basis of voice calling and text messaging. Malaysian MP users (N = 187) completed four questionnaires (Mobile Phone Usage Questionnaire, Big Five Inventory, Interaction Anxiousness Scale and UCLA Loneliness Scale) on paper or online via a web-link. Multiple regression analyses revealed that personality, SA and loneliness broadly predicted preferences for voice calling or text messaging. Further analyses examining the predictability of time spent on voice calls/text messaging and number of people called/exchanged text messages also revealed some significant findings in regards to the openness-to-experience personality dimension, loneliness and SA. The findings of this research have important implications to tailoring the delivery of psychological services to individuals diagnosed with chronic loneliness and SA.