This research aimed to develop a deeper understanding of trust and non-profit agency website design, and specifically focussed on the ‘Donate Now’ button. Two experiments investigated the effects of varying levels of consumer certainty, manipulated by providing varying levels of donation relevant information on the web homepage donation buttons, on aid agency trust and donation compliance. Both experiments were based on Study 1, a preliminary survey of website donation button design. Experiment 1 investigated the effects of iconic manipulation of the ‘Donate Now’ button. Results suggested that varying levels of consumer certainty through iconic manipulation of the website donation button design did not effect aid agency trust and donation compliance. Experiment 2 extended the research of Burt and Dunham (2009) to investigate the effects of varying consumer certainty levels through the provision of crisis/need and response photographs on the donation buttons. Results suggested that whilst there was no effect of level of certainty on donation compliance, there was an effect on aid agency trust. Participants’ rated aid agency trust was increased to the greatest extent in the level of greatest certainty, when the donation button contained photographs of both the crisis/need and agency response. Collectively, these results suggest that aid agency trust can be enhanced through the considered manipulation of donation button design. Subsequently photographic images may be a more effective means with which to portray donation-relevant information and reduce uncertainty. Furthermore, in both experiments results showed that those individuals who reported higher aid agency trust also reported significantly higher donation intention. Thus, the current research has implications for the non-profit sector, suggesting that whilst the internet is a viable fundraising tool, the commercially driven process of online donation generation should not be isolated from the psychological concept of trust.