By-elections in Singapore

By-elections in Singapore are elections held to fill seats in the Parliament of Singapore that fall vacant in between general elections, known as casual vacancies. In the past, the Government of Singapore took the position that the Prime Minister had discretion whether or not a by-election should be called to fill a casual vacancy in a Single Member Constituency, and could leave a parliamentary seat unfilled until the next general election.

Source: Wikipedia — By-elections in Singapore (CC BY-SA 4.0)