Administrative linked data offer promising research avenues for studying internal mobility. Based on multiple quite exhaustive and accurate data collections, administrative linked data are especially well-suited for studying migration. They can be exploited as representative panel data, allowing longitudinal analysis from micro to macro level over long periods of time. Complete enumeration and systematic follow-up give the opportunity to study internal migrations, while taking into account the specificities of international migration trajectories. This contribution use French administrative linked data as a case study to show of these data can help studying internal migration by considering all individuals leaving a specific place over time, regardless of their final destination. Measuring out-migration from French municipalities with the French Demographic Sample (EDP) helps correcting the underestimation of mobility ratio, especially those of immigrants: they are much more mobile than natives once all trajectories are taken into account.