Objectives: In France, cancer registries cover only 20% of the population. To estimate the incidence (I) of cancer at the departmental level, hospital stays reported through the Medical Information Systems Program (PMSI) and data on long-term conditions (ALD) can be used. By applying the approach used for regional incidence estimates for 2008–2010, the objective of this study was to provide departmental incidence estimates for the same period. Method: The principle of the departmental estimate consists of applying the ALD/I (or PMSI/I) ratio from the registry area to the departmental ALD (or PMSI) data. The use of a decision tree made it possible to determine whether a cancer site could be included in a departmental estimate. Results: Among men, departmental incidence estimates were calculated for 8 of 19 eligible sites, including 5 based on ALD data and 3 on PMSI data. Among women, departmental estimates were calculated for 8 of 21 eligible sites, including 1 based on ALD data and 7 on PMSI data. Interdepartmental disparities in incidence are evident for sites where personal risk factors (tobacco, alcohol) are significant and well-known (lip-mouth-pharynx, esophagus, larynx, lung). Risk factors other than tobacco or alcohol consumption result in lower excess risks and are likely more spatially diffuse. Conclusion: This study presents the first structured approach leading to departmental incidence estimates. Spatial disparities in incidence concern cancers linked to smoking and alcohol; however, for these cancers, the possible role of other risk factors (occupational, environmental, etc.) should not be overlooked. Geographical disparities and gradients for other cancer sites should be interpreted with caution.