How long is a senator is in term of office?

Answer 1

There is no fixed term of office for Senators in Australia. A Senator's term starts on the day of a general election for the House of Representatives and ends the day before the next such election day, which could be anywhere between two and a half years up to six years.

However, the reason there is no fixed term is that Parliament does not run to a fixed schedule: it is entirely up to the government of the day when they will hold an election within certain parameters. A Senator is usually there for two parliaments, but the parliament can be almost any length of time. The Governor general has the final say on when the election will occur.