This paper seeks to examine the impact of electoral websites on young people's electoral engagement, focusing on the 2012 London Mayoral and US Presidential election. It does so by employing an innovative research design to connect the supply and demand side of the equation, including quantitative content analysis and an innovative experiment that allows for qualitative evaluation as well as for an examination of the causal effects of exposure to specific websites. The three specific types of websites examined in each election are: youth mobilization websites, the official candidate campaigning websites and Vote Advice Applications. We explore the effects of these websites on behavioural, cognitive and attitudinal aspects of engagement: likelihood of voting, attention to news, internal and external efficacy and political trust. Research to date on the effect of electoral websites on young people has produced mixed results on political engagement and efficacy (e.g. Tedesco, 2007; Xenos and Kyoung, 2008). We find no direct effect on young people for voting across the websites but we do find a number of significant effects across the other variables, which are occasionally found only amongst those with the lowest pre-existing levels of engagement. This leads us to conclude that the web can create a pathway to participation for young people but this is dependent on the specific type and attributes of the website, the election context and the young person themselves.