PurposeThe purpose of this paper is to investigate the moderating effect of organizational policy on the relationship between online social networking (OSN) and job performance of IT professionals engaged full‐time in offshore outsourced IT firms in Sri Lanka.Design/methodology/approachSurvey methodology was used and a random sample of 215 respondents who fulfilled the selection criteria set for the study, responded. To examine the hypothesized relationships, factor analysis and multiple regression were used.FindingsIt was found that individuals engaged in online social networking while at work enjoy several benefits such as solving work‐related problems collaboratively. However, individuals also suffer from several drawbacks, which could be mainly categorized into two in terms of interference to job tasks and interference to workplace. Further, it was found that online social networking has significant effects on individual job performance; organizational policy moderates the relationship between online social networking and job performance.Originality/valueAlthough online social networking has attracted a substantial amount of media attention over the last few years empirical research attempts have not taken off worldwide. Therefore, the influence of online social networking on employee job performance would be of interest to academics and practitioners worldwide. It is expected that the findings of this study will provide insight into benefits, challenges and issues associated with OSN to allow individuals, organizational leaders, and IT decision‐makers to better understand and utilize online social structures for success. Further, it is expected that the findings of this study will be a source of general guidance in stimulating future research in this area.