OBJECTIVES: The aim of the study is to estimate the pension costs (social security system in Italy is financed by public expenditure) induced by patients with central nervous system (CNS) and specifically for multiple sclerosis (MS) between 2009 and 2015. METHODS:  We analysed the database about the approved claims and the mean cost per benefit of the National Institute of Social Security (INPS) for three types of social security benefits: incapacity pensions (for people without work ability), disability pensions and disability benefits (for people with reduced work ability). From this data we have estimated the total benefit provided and the total costs for each disease. A probabilistic model with a Monte Carlo simulation was developed in order to estimate the total benefits provided and costs. RESULTS:  The model estimated a total of incapacity pensions paid from 2009 to 2015 of about 90,000 (13,000 on average annually with a mean annual increase of 1%) corresponding to € 1.1 billion (annual mean value of € 165 million with a mean annual increase of 2%); a total of disability pensions paid of about 755,000 (180,000 on average annually with a mean annual decrease of -10%) for a cost of € 5.3 billion (average annual of € 763 million with a mean annual decrease of -9%) and a total of disability benefits provided of about 212,000 (annual mean of 30,000 with a mean annual increase of 5%) corresponding to € 1.8 billion (€ 255 million on average annually with a mean annual increase of 7%). CONCLUSIONS:  The most important indirect costs in Italy from 2009 to 2015 was represented by disability pensions (64% of the total cost), followed by disability benefits (21% of total indirect cost). A better prescription appropriateness and rapid access to innovative treatments would reduce the costs incurred by the social security system.