OBJECTIVE: Within the “Pistoia Project(PP)” (a large screening study whose objective is the identification of hypertensive disease, organ damage, and related risk factors to activate actions of primary and secondary prevention), we conducted a preliminary cost of illness analysis, to investigate if age, gender and severity of hypertension could influence the use of healthcare services, and therefore have a direct impact on costs. METHODS: 45 patients’ records were randomly selected from the GPs’ screening forms of the PP: patients were either hypertensive or normotensive under treatment. Using healthcare codes, we computed hospital data (DRG code and cost), while pharmaceutical consumption (units and cost) was retrieved from the pharmaceutical regional database and the local Hypertension Centre retrieved number and typology of specialist consultations and procedures. Indirect costs were partly calculated from social security system certificates, and partly estimated under the hypothesis that each hospital stay and each specialist visits imply a loss of working days. RESULTS: in 1997, 45 patients generated a total cost of Lit. 29.9 million with an average cost per patient per year of Lit. 664,282. Pharmaceutical care accounted for 45% of total cost, followed by hospital admissions (34%), productivity losses (16,4%) and specialist visits and procedures (4,3%). CONCLUSIONS: this preliminary analysis has demonstrated the potential of such an instrument to evaluate the cost of managing hypertension in a large area as the Pistoia province. Further research is needed on larger samples to identify patterns of resource use and to evaluate the influence of illness severity on the total cost of this disease.