PurposeThe purpose of this paper is to systematically review and analyse the critical challenges and barriers of e‐government adoption. Such review aims to suggest the salient facts about the issues of successful implementation or adoption of the e‐government services under different circumstances to the researchers.Design/methodology/approachA total of 78 relevant research papers reviewing and analysing the challenges, barriers, and critical success factors were selected from a set of overall 448 articles on e‐government adoption research. These studies were comprehensively reviewed to examine some of the most significant supply and demand‐side challenges, barriers, and critical success factors explored by different studies in this context.FindingsThe findings indicated that technological barriers, lack of security and privacy, lack of trust, lack of resources, digital divide, poor management and infrastructure, lack of awareness, legal barriers, lack of IT infrastructure, and resilience were among some of the most commonly experienced challenges and barriers across the relevant studies. Moreover, it was also found that challenges and barriers associated with supply‐side (i.e. implementation) (C=53) were almost three times to the one applied to the demand‐side (i.e. adoption) (C=18). Furthermore, it was also found that citizen's satisfaction, information accuracy, security, and privacy were some of the critical factors for the success of e‐government initiatives.Research limitations/implicationsThis research only reviews the challenges, barriers and critical success factors and leaving apart many other research themes such as impact, digital divide, security, privacy, trust, and risk of e‐government adoption. Moreover, the theoretical and methodological paradigm of this research have not been explored.Originality/valueThis paper presents a comprehensive review of the challenges, barriers, and critical success factors of the e‐government adoption research both with regard to supply as well as demand side. Such review allows us to provide not only a brief account of the issues experienced in the e‐government research, but also prescribes the guidelines for the governments to consider certain facts before successfully implement their e‐government initiatives. Such a comprehensive review of e‐government adoption literature has not been performed earlier.