Vårbyfjärden (Swedish for "inlet of Vårby") is a strait in south-eastern Lake Mälaren south-west of Stockholm in Sweden. Vårbyfjärden separates Ekerö island and Ekerö Municipality north of it, from Södertälje and Huddinge Municipalities south of it and Stockholm Municipality on its western side. South of Vårbyfjärden is Albysjön,