The aim of this study is to analyse to what extent Local Government entities in Portugal (municipalities and municipal companies) are taking advantage of the Internet
potential for information disclosure, thus considering it as an instrument to enhance transparency towards the citizens. In order to fulfil this goal, an evaluation model (transparency index) was used, taking into account open government data principles proposed by several bodies and researchers. The model, which evaluates visibility,
presentation format and availability mode of a set of information items, was applied (in 2010) to 306 Portuguese municipalities and 190 municipal companies. Data shows
that the level of transparency of the entities that took part in this study is, on the whole, low, especially in the case of municipal companies. Particularly, findings reveal that the way information is made available does not tend to promote citizens’ independent analysis.