Single Transferable Vote

With the Single Transferable Vote (STV), the mix of opinions in parliament matches the strength of their support in the country, and representatives - for example, Members of Parliament - have a strong connection to their local area.

Single Transferable Vote STV

What is the Single Transferable Vote?

The Single Transferable Vote (STV) is a form of proportional representation created in Britain. Northern Ireland, the Republic of Ireland, Malta, Scotland and Australia use this system for some or all of their elections. In America, it is often referred to as ‘ranked-choice voting in multi-member seats’, in Australia they call it ‘Hare-Clark’.

How does the Single Transferable Vote system work?

Rather than one person representing everyone in a small area, bigger areas elect a small team of representatives, such as 4 or 5. These representatives reflect the diversity of opinions in the area.

On election day, voters number a list of candidates. Their favourite as number one, their second favourite number two, and so on. Voters can put numbers next to as many or as few candidates as they like. Parties will often stand more than one candidate in each area.

The numbers tell the people counting to move your vote if your favourite candidate has enough votes already or stands no chance of winning.

How it’s counted

To get elected, a candidate needs a set amount of votes, known as the quota. The people counting the votes work out the quota based on the number of vacancies and the number of votes cast.

Each voter has one vote. Once the counting has finished, any candidate who has more number ones than the quota is elected. But, rather than ignore extra votes a candidate received after the amount they need to win, these votes move to each voter’s second favourite candidate.

If no one reaches the quota, then the people counting the vote remove the least popular candidate. People who voted for them have their votes moved to their second favourite candidate. This process continues until every vacancy is filled.

Effects and Features

The Single Transferable Vote is an electoral system that puts the power in the hands of the public. Evidence from Scotland and Ireland suggests voters use it in quite sophisticated ways.

Voters can also choose between candidates from the same party or different parties. This means voters can elect all MPs based on their individual abilities.

Voters can also vote for independent candidates without worrying about wasting their vote. Ireland has many independent MPs, as do some Scottish councils.

Constituencies are more natural, covering a whole town or a county. This creates a recognisable local link, and gives voters a choice of representatives to talk to.

Examples

After the 2020 Irish General Election, we spoke with people who have voted with Ireland’s STV system and under Westminster’s First Past the Post system. You can read about how they felt about STV in our blog.

Example Election - 3 Seat Video

To calculate the quota: There were 109,525 valid votes cast and three seats to be filled. So, 109,525 divided by four (because we have three seats, plus one), then plus one = 27,382

  1. John has easily reached the quota so is elected. His surplus votes are transferred based on the instructions on the ballots
  2. Many of John’s supporters also liked Aliyah. She gets enough of the transferred votes to be elected.
  3. Aliyah’s surplus votes are transferred but nobody has enough to be elected.
  4. Helen has been eliminated and the votes she won are transferred.
  5. Paul is also eliminated
  6. It’s now impossible for Sally to win, so Kwame wins the last seat.

Multi-Member Constituency Example

London with 3 and 4 seat STV constituencies
The white lines are the borders of London’s current constituencies, the different colours are potential multi-member constituencies.

Rather than having 3 single-member constituencies next to each other, you have one bigger constituency that elects 3 MPs. To better fit the natural, administrative and locally recognised boundaries, some of the new multi-member constituencies elect 3 and some 4 MPS. Constituencies designed by Lewis Baston. 

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