This study aims to investigate the impact of off-page communication factors on success of crowdfunding campaigns. While previous research mainly focused on on-page communication factors, relevant research on the impact of off-page communication factors related to additional website visibility and external social media remains scarce. To address this gap, the authors examine the impact of search engine optimization (SEO) actions taken on an additional website and explore influence of the use of external social media on rewards-based crowdfunding success, as it is argued to be the dominant online model. They perform a cross-sectional study of a randomized sample of 1,791 campaigns on KissKissBankBank, the major crowdfunding platform in Europe. The results reveal that (1) SEO actions taken on the additional website enhance success of the crowdfunding campaign, and (2) there are important connections between the use of external social media and success of crowdfunding campaigns. Taken together, these results contribute to adequate decision making among project initiators, backers, and platforms owners.