This paper investigates how citizens' uncertainty in e-government services can be managed. First, we draw from uncertainty reduction theory, and propose that transparency and trust are two key means of reducing citizens' uncertainty in e-government services. Second, we identify two key sets of relevant drivers of e-government service use: (1) information quality characteristics, i.e., accuracy and completeness; and (2) channel characteristics, i.e., convenience and personalization. We propose that the means of uncertainty reduction, information quality characteristics, and channel characteristics are interrelated factors that jointly influence citizens' intentions to use e-government. We tested our model with 4,430 Hong Kong citizens' reactions to two e-government services: government websites and online appointment booking. Our results show that the information quality and channel characteristics predict citizens' intentions to use e-government. Furthermore, transparency and trust mediate as well as moderate the effects of information quality and channel characteristics on intentions. A follow-up survey found that citizens' intentions predict use and ultimately, citizens' satisfaction.