The paper reports on long time testing of reinforcement corrosion in normal and total-lightweight concretes exposed to cycles consisting of 4 phases: chloride salt fog, drying, sulphate solution immersion, drying. Potential monitoring evidenced a passive condition for all reinforcements embedded in normalweight concretes. The initiation of the corrosive attack in total-lightweight concretes could not be evidenced, although low potential values were found on corroding reinforcements.