Sundby may refer to:
Places
editDenmark
edit- Sundby, Copenhagen, a district in Copenhagen
- Sundby, Lolland, a satellite town of Nykøbing Falster on Lolland
- Nørresundby, a town on North Jutlandic Island
Sweden
edit- Sundby, Sweden, a locality on Ekerö in Stockholm County
- Sundbyberg Municipality, Sweden
People with the surname
edit- Martin Johnsrud Sundby, Norwegian cross-country skier
- Ragnhild Sundby (1922–2006), Norwegian zoologist