Information transparency is a key aspect of the Corporate Social Responsibility (CSR) strategy. The new information and communication technologies, such as the Internet, allow companies to disseminate relevant corporate information to different stakeholders and society, promoting voluntary online transparency. The analysis of social responsibility information published on corporate websites permits, among other issues, the development of disclosure and transparency indexes that facilitate comparisons between companies, and the assessment of potential drivers of the transparency strategy. In this sense, this study has two main objectives: (1) To develop a measurement index of voluntary online transparency, and (2) to identify relevant factors that influence on such transparency. The empirical research was carried out by analyzing the websites of a 176 large Spanish retail companies. Regression analysis was used to test the proposed hypotheses. The results obtained show that online voluntary transparency is encouraged by the implementation of CSR principles in store management and by the particular type of contributions in which the social commitment of the retail is materialized (monetary versus non-monetary), as well as by the fact that employees and/or society as a whole represent the main beneficiaries of CSR activities
