Purpose – The purpose of this study is twofold: to evidence the disclosure practices of Spanish companies in relation to a voluntary typology of strategic information; and to determine the factors that explain these practices. Among the factors considered, the study seeks to focus on the role of the Board of Directors in depth. According to Agency Theory, strategic information has positive consequences on external funds costs. On the other hand, Proprietary Costs theory limits these practices, given that they can lead to competitive disadvantages. Design/methodology/approach – First, online strategic information disclosure practices are analysed by examining non-financial quoted Spanish firms. A disclosure index is created, and subsequently, certain factors related to corporate governance – Activity, Size and Board Independence – as well as other factors traditionally analysed, are used to explain the volume of strategic information disclosed on the internet. Findings – The results indicate that Spanish companies, on average, give out little strategic information, mainly related to objectives, their mission, and the company's philosophy. “Company annual planning” and “Information on risks” are scarcely disclosed. The findings also emphasise that companies where the Chairperson of the Board is the same person as the CEO and, moreover, in which there is a lower frequency of meetings, disclose a greater amount of strategic information on their web sites. Practical implications – The findings suggest that the disclosure of strategic information is a decision taken by executives with the aim of satisfying the demands of creditors and investors. The Board of Directors represents the shareholders' interests, but it does not participate in strategic decision-making disclosure, maybe due to the fact that the proprietary costs lack influence. Originality/value – The link between corporate governance and strategic information disclosed online has scarcely been analysed in previous literature. This study provides interesting insights into how several Board characteristics can affect the disclosure of strategic information on the internet.