Family name Birgir (Birgir 
) , in the world, is a very rare cognomen. The surname Birgir is habitual in Iceland, where it is quite a common surname, Chile, where it is an extremely rare surname, and Germany. Not in comparison with a country's population, the name is most common in Iceland, Germany, and India. More frequently, Birgir is the forename as well as the last name.
Sson, Einarsson, Olafsson, Óskarsson, Ólafsson, Þórisson, Magnusson, Sigurðsson, Stefánsson, Pétursson, Guðmundsson, Finnbogason, Sigurdsson, Sigurjónsson, Steinarsson, Brynjolfsson, Kristinsson, Ragnarsson, Gunnarsson, Thorarinsson, Haraldsson, Gudmundsson, Jóhannsson, Reynisson, Karlsson, Bjarnason, Arson, Rnsson, Mundsson, Lafsson, Snorrason, Arnason, Arnarson, Breiðfjörð, Poulsen, Jonsson, Johannesson, Jónsson, Nielsen, Harðarson, Hauksson, Helgason, Ómarsson, Magnússon, Agustsson, Baldursson, Birgisson, Björnsson, Tursson, and Valdimarsson