Stroke is the second most common cause of death in the world. The aim of this study is to estimate stroke's direct costs and productivity losses in Italy from a societal perspective and to explain cost variability. A prospective observational multicentre cost of illness study was designed. Four hundred and forty-nine consecutive patients admitted because of acute first-ever stroke in 11 Italian hospitals were enrolled. Costs and outcomes were assessed at patients' enrollment, and at 3, 6 and 12 months after discharge. Overall, social costs in the first six months following the attack were euros 11,600 per patient; 53% of this was health care costs, 39% non-health care costs and the remaining 8% productivity losses. Age, level of disability and type of hospital ward were the most significant predictors of six-month social costs. The acute phase counted for more than 50% of total health care costs, leaving the remaining 50% to the post-acute phase, indicating that follow-up should be on the agenda of policy makers also.