singlemember

Single-member districts, also referred to as single-member constituencies, are electoral districts that elect exactly one representative to a legislative body. Voters in each district cast a single vote for individual candidates, and the candidate who receives the most votes wins the seat. In many countries the winner is decided by simple plurality, while some systems require a majority and use run-off elections or ranked-choice ballots to determine the winner.

Single-member districts are a hallmark of first-past-the-post and similar plurality-based electoral systems. They are widely used in countries such as the United States (House of Representatives), the United Kingdom (Parliament), Canada (House of Commons), and India (Lok Sabha). By contrast, proportional representation and multi-member districts allocate seats to reflect party vote shares rather than geographic districts, influencing party systems and representation differently.

The use of single-member districts shapes political strategy, accountability, and policy outcomes. They can promote geographic representation and stable party competition, but may also magnify regional disparities or underrepresent smaller parties. Boundary drawing, or gerrymandering, can affect electoral results without changing national vote shares. Some jurisdictions implement alternative voting methods within single-member districts, such as instant-runoff or ranked-choice voting, to ensure the winner has broader support.