byelection

A by‑election, also known as a special election, is an election held to fill a political office that has become vacant during a term of office. Vacancies may arise for a variety of reasons, including the death, resignation, disqualification, or appointment of a sitting member to another position. The primary purpose of a by‑election is to ensure that the electorate continues to have representation in the legislative body or other governmental institution.

The timing and procedures for a by‑election are established by the governing body’s rules or the country’s constitution. In many parliamentary systems, a by‑election must be called within a specified period after a seat becomes vacant, often by an order of the presiding officer or by notification from an electoral commission. Candidates typically must meet the same eligibility requirements as those running in general elections, though the campaign cycle is normally shorter.

By‑elections can serve as indicators of public sentiment between general elections and may influence the balance of power in a closely divided legislature. In the United Kingdom, for example, a by‑election in a marginal parliamentary constituency can shift seat counts in the House of Commons. The process in other countries follows similar principles but varies in electoral laws and administrative arrangements.