Upon entering the internal sea waters and territorial sea of the Republic of Croatia, the vessel's captain is required to proceed via the shortest route to the nearest port open to international traffic in order to undergo border control and obtain a vignette at the harbormaster’s office or its branch office.

The vignette is a document that proves the vessel's arrival has been reported, that the conditions for navigation in the Republic of Croatia have been met, and that fees for navigation safety, lighthouse service, nautical information chart, and the administrative fee have been paid.

The vignette is valid from the date of issue until the end of the current calendar year. A vignette is required for any vessel that is 3 meters or longer, as well as for vessels shorter than 3 meters with a total engine power of 5 kW or more.

Vessels powered solely by oars, regardless of their length, are not required to have a vignette.