Autonomous vehicles will be a key component of the sustainable cities and transport systems of the future. However, there is little data available on effective methods of communicating with the public about these benefits to optimise uptake and achieve their sustainability potential. The aim of this exploratory study was to assess outcomes associated with exposure to various messages communicating proposed benefits of autonomous vehicles. Australians aged 16+ years (n = 1053) responded to two online surveys administered two weeks apart. The instruments included items relating to demographic attributes, driving factors, and attitudes to autonomous vehicles. Respondents were randomised to one of five messages referring to efficient travel time, economic savings, saving lives, mobility for the elderly and disabled, and job opportunities. Messages relating to saving lives and providing mobility for the elderly and disabled performed best, especially in terms of presenting a strong argument (62% agreement) and believability (67% agreement), respectively. The results provide initial evidence that public awareness communications could favourably influence attitudes to autonomous vehicles, potentially enhancing uptake rates to yield corresponding benefits. This information will be of value in countries where the roll-out of autonomous vehicles is a strategic priority to achieve sustainable cities and transport systems.