Cognomen Sidse (Sidse 
) , globally, is an extremely rare last name. The cognomen Sidse is characteristic of Southern Europe, particularly Spain, where it is an extremely rare surname. Much more frequently, Sidse is the forename as well as the last name.
Buhn, Nielsen, Ellegaard, Mogensen, Schjøtz, Andersen, Petersen, Pedersen, Jakobsen, Jeppesen, Thestesen, Tjellesen, Mortensen, Mikkelsen, Soerensen, Sørensen, Rasmussen, Thomassen, Henriksen, Kristensen, Jørgensen, Christensen, Thomsen, Linnæs, Knudsen, Coppolo, Lund, Duusgaard, Lange, Holte, Olsen, Udsen, Madsen, Sommer, Stavad, Bjørn, Kristiansen, Powell, Larsen, Jensen, Thorup, Egholm, Hansen, Hjorth, Wonson, Ørndrup, Malling, Møller, Rensen, and Christiansen