Cognomen Eysteinn (Eysteinn 
) , throughout the world, is an extremely rare family name. Predominantly, Eysteinn is the forename as well as the last name.
Nason, Gunnarsson, Kristinsson, Hilmarsson, Langeland, Sigurðsson, Einarsson, Erlendsson, Jónasson, Juliusson, Guðnason, Helgason, Elvarsson, Jónsson, Jonsson, Leifsson, Finnsson, Lester, Bjarni, Arason, Gunnlaugsson, and Þórðarson