After breeding, long-distance migrants may either immediately depart for autumn migration, or spend a pre-migration period during which they disperse over various distances, or even stay in the breeding area. The Common Tern (Sterna hirundo) is a long-distance migrant that lays one clutch per season. In the case of breeding failure, it may lay a replacement clutch at the same or different breeding patch. We studied short- and medium-distance movements of Common Terns from two freshwater and two marine colonies in Croatia between May and August. Thirty Common Terns were tagged with remote download GPS devices, and among these, 11 showed dispersal movements. The majority of successful breeders left the breeding area with no medium-distance dispersal movements recorded. After experiencing breeding failure, some birds exhibited high site fidelity and immediately started laying replacement clutches at the same or neighboring breeding patches, while others moved away from the colony, covering distances of up to 200 km, and during that period visited several conspecific colonies. For birds that dispersed, we calculated daily travel distances and maximum distances from the breeding colony. Birds breeding in Croatia visited Italy, Slovenia, and Hungary. Knowledge about postbreeding movements may help understand population connectivity, as well as reveal the spread of pathogens. This is especially important in light of the recent outbreaks of high-pathogenicity avian influenza among seabirds. Funding organization: Croatian Science Foundation (IP-2020-02-8793)