OBJECTIVES: To assess the impact of inflammatory bowel diseases (IBD) in the Italian general population: incidence and time trends from 2003 to 2009, as well as population characteristics. METHODS: A retrospective observational study was conducted in Lombardy, an Italian region with about 10 million of inhabitants, using healthcare administrative databases of the national healthcare system (HS) which provides universal coverage. The main administrative databases were integrated in a data warehouse called DENALI using probabilistic record linkage. New cases of Crohn’s Disease (CD) and Ulcerative Colitis (UC) were identified in the adult population between January 1st, 2003 and December 31st, 2009. Annual age-standardized incidence rates were computed separately for CD and UC using the population living in Lombardy at 2001 census. Moreover we evaluated patients’ baseline main characteristics, coexisting chronic conditions and survival at December 31st, 2009 . RESULTS: The annual incidence rate per 100,000 person-years of IBD was 15.6 (95%CI 15.2-15.9); UC and CD incidences were 9.7 (9.4-10.0) and 5.9 (5.7-6.1) respectively.  Incidence rates of both diseases were higher in men than in women. CD incidence was highest in subjects aged 20-24 (9.2, 95%CI 8.1-10.2) and decreased with age, while UC incidence was stable in the 20-65 year-old population. No time trends in UC and CD incidences were observed from 2003 to 2009, both in the whole study population and in gender and age-specific subgroups. The mean age at CD diagnosis was 44 years (±16.6 sd), which was lower than that at UC diagnosis (46 ± 16.6, p<0.0001). During a mean follow-up time of 3.4 years (± 2.0) 2.2% of IBD patients died. CONCLUSIONS: Our study provides updated estimates on current epidemiology of IBD in Italy. IBD incidence in Lombardy is lower than in northern Europe and the data confirm that UC incidence is higher than that of CD.