Nykøbing Falster is a city on the island of Falster in southern Denmark. It has a population of 16,927. Including the satellite town Sundby on the Lolland side, with a population of 3,178, the total population is 20,105.

Falster is an island in south-eastern Denmark with an area of 486.2 km2 (187.7 sq mi) and 43,398 inhabitants as of 1 January 2010. Located in the Kattegat, Belts and Sound area, it is part of Region Zealand and is administered by Guldborgsund Municipality. Falster includes Denmark's southernmost point, Gedser Odde, near Gedser.