Objectives: Addiction to social networking sites (SNSs) is an international issue with numerous methods of measurement. The impact of such addictions among health science students is of particular concern. This study aimed to measure SNS addiction rates among health sciences students at Sultan Qaboos University (SQU) in Muscat, Oman. Methods: In April 2014, an anonymous English-language six-item electronic self-reporting survey based on the Bergen Facebook Addiction Scale was administered to a non-random cohort of 141 medical and laboratory science students at SQU. The survey was used to measure usage of three SNSs: Facebook (Facebook Inc., Menlo Park, California, USA), YouTube (YouTube, San Bruno, California, USA) and Twitter (Twitter Inc., San Francisco, California, USA). Two sets of criteria were used to calculate addiction rates (a score of 3 on at least four survey items or a score of 3 on all six items). Work-related SNS usage was also measured. Results: A total of 81 students completed the survey (response rate: 57.4%). Of the three SNSs, YouTube was most commonly used (100%), followed by Facebook (91.4%) and Twitter (70.4%). Usage and addiction rates varied significantly across the three SNSs. Addiction rates to Facebook, YouTube and Twitter, respectively, varied according to the criteria used (14.2%, 47.2% and 33.3% versus 6.3%, 13.8% and 12.8%). However, addiction rates decreased when workrelated activity was taken into account. Conclusion: Rates of SNS addiction among this cohort indicate a need for intervention. Additionally, the results suggest that addiction to individual SNSs should be measured and that workrelated activities should be taken into account during measurement.