The user experience of e-Government is regarded as important for e-Government adoption and effectiveness, yet there is no agreement as to the dimensions of the user experience. Hence, this study seeks to develop a scale for the measurement of the perceptions of the users' experience of e-Government services. Since there is particular concern regarding the success of e-Government in developing countries, the e-services offered by the Nigeria Immigration Service (NIS) were chosen as the focus for this study. Drawing on various strands of previous research related to the user experience of e-Government and other websites, including research on technology adoption, customer satisfaction and service quality, a broad based research instrument was developed to capture perceptions of the user experience with the NIS website, as well as other key demographic data. In order to facilitate access to service users located in different countries an on-line questionnaire-based survey was conducted, using a snowball sample; 351 completed questionnaires were collected, and analysed using SPSS. All respondents identified themselves as having used the NIS portal, with 50% reporting their main place of residence as being Nigeria, and the remainder being resident in various other countries. Whilst the questionnaire design was informed by previous research in the fields of customer satisfaction and technology adoption, the exploratory factor analysis generated an e-Government user experience scale that both confirmed the importance of some dimensions identified by other researchers, and identified new factors. Factors identified were: security and support, content and information, ease of use, benefits, barriers, convenience, trust and website quality. Findings are discussed with reference to previous research and recommendations for practice and further research are offered.