When does a by-election typically occur?

Okay, so by-elections are all about filling unexpected vacancies in the House of Commons. Think of it like this: in a general election, everyone votes for their MP, and that person is supposed to represent them for the next few years. But life happens! Sometimes an MP might decide to step down – that's a resignation. Or, sadly, an MP might pass away while in office. When either of these things occurs, the seat they held suddenly becomes empty before the next scheduled general election. To ensure that the constituency continues to have representation in Parliament, a by-election is called. It's essentially a mini-election just for that specific area, allowing the people there to choose a new MP to fill the vacant spot. It's important to remember that by-elections only happen when an MP leaves their post prematurely, not just because it's been a certain amount of time.