The most delicate sea tern with a very long tail. Their bill is shorter than that of the Common Tern.

While the Common tern is slim and elegant, the Arctic Tern is even more so, with a long tail and long, slender, attenuated wingtips. Usually much less common inland, they occasionally visit reservoirs on migration. Since they spend the summer so close to the Arctic, and the winter at sea in the Antarctic, these terns are said to experience more constant daylight than any other species.