How many votes are needed for a bill to pass the House of Representatives and the Senate?

Interesting question Liliana. A majority vote is needed for a bill – a proposed law – to pass both the Senate and House of Representatives. Not all senators or members need to be present for the vote. The bill is passed if a majority – more than half of senators or members present in either the Senate or House – vote for it.

However, a bill to change the Constitution – the rulebook of our nation – can only be passed by an absolute majority. This means a majority of the whole number of Senators or members of the House.

In both houses, two different kinds of votes – a vote on the voices and a division – are used to decide if a bill has passed. A vote on the voices is held first. The President of the Senate or Speaker of the House of Representatives asks members of parliament to cast their vote for the bill by saying 'aye' or 'no'. The President or Speaker decides which response has more support and announces the result. If the result is challenged by more than one member of parliament, a division – a formal counted vote – is held.

In the Senate, at least 19 senators – one quarter of the total number of senators – must vote in a division for it to count. In the House, 30 members must be present – one fifth of the total number of members. This is called quorum and is the minimum number of members required for the Senate and House to meet.

If 19 senators are not present for a division, the President of the Senate can adjourn – suspend – the Senate until the next sitting day. This gives senators a chance to form a quorum, so the division can be held again. Under House standing orders, the Speaker can adjourn the House until a quorum can be formed.

For a bill to become law, it must be agreed to by the Senate and House of Representatives and receive Royal Assent by being signed by the Governor-General.