Single Transferable Vote

The Single Transferable Vote (STV)
How electoral systems work

Single Transferable Vote

Where is STV used?

• All elections in the Republic of Ireland, except elections for the presidency and by-elections which are both conducted using the Alternative Vote.
• Assembly, European and local government elections in Northern Ireland.
• Local elections in Scotland.
• The Australian Senate.
• The Tasmanian House of Assembly.
• The indirect elections to the Rajya Sabha, the upper house of India's federal Parliament.
• All elections in Malta.
• Various local authorities in New Zealand.
• Many UK student unions (it is promoted by the National Union of Students as the fairest electoral system), the Church of England and many other private organisations.

How does the Single Transferable Vote work?

The Single Transferable Vote (STV) is a form of proportional representation which produces a proportional parliament with local representation and the direct election of individuals. Each constituency sends a team of MPs that represent the diversity of opinion in that constituency to parliament. 

In the polling station, voters put numbers next to candidates in order of preference. To get elected, candidates need to reach a set share of the votes, determined by the number of positions to be filled.

Each voter gets one vote, which can transfer from their first-preference to their second-preference, so if your preferred candidate has no chance of being elected or has enough votes already, your vote is transferred to your second choice candidate in accordance with your instructions. STV thus ensures that very few votes are wasted, unlike First Past the Post, where only a small number of votes actually contribute to the result.

To find out exactly when votes are transferred or how to set the share of votes needed to get a candidate elected, read our pamphlet What is STV?

STV in action

Pros and cons of the Single Transferable Vote

The case for

The arguments against

STV gives voters more choice than any other system. This in turn puts most power in the hands of the voters, rather than the party heads, who under other systems can more easily determine who is elected. Under STV MPs' responsibilities lie more with the electorate than those above them in their party.

In sparsely populated areas, such as the Scottish Highlands, STV could lead to very large constituencies.

Fewer votes are 'wasted' (i.e. cast for losing candidates or unnecessarily cast for the winner) under STV. This means that most voters can identify a representative that they personally helped to elect. Such a link in turn increases a representative's accountability.

The process of counting the results takes longer under STV, meaning that results cannot usually be declared on the same night as the vote took place. This can be combated with electronic ballot paper scanners.

With STV and multi-member constituencies, parties have a powerful electoral incentive to present a balanced team of candidates in order to maximise the number of higher preferences that would go to their sponsored candidates. This helps the advancement of women and ethnic-minority candidates, who are often overlooked in favour of a 'safer' looking candidate.

A voting system that allows voters to rank candidates is prone to so-called 'Donkey voting', where voters vote for candidates in the order they appear on the ballot. Names on ballot papers have to be batch printed using a method known as Robson Rotation.

STV offers voters a choice of representatives to approach with their concerns post-election, rather than just the one, who may not be at all sympathetic to a voter's views, or may even be the cause of the concern.

Voters only tend to come into contact with candidates at election time, whereas people in the party know them much better. It could be argued, therefore, that a system that allows a political party to parachute its preferred candidates into safe seats is better than one that leaves the choice more in the hands of the voters.

Competition is generally a good thing and competition to provide a good service to constituents is no different.

In large multi-member constituencies, ballot papers can get rather big due to the amount of candidates.

Parliament is more likely to be both reflective of a nation's views and more responsive to them. Parties are broad coalitions, and can have a markedly broad range on lots of issues. With only one party person per constituency, the representatives elected may well not reflect the views of their electorate. STV would help voters to pick a candidate who most closely reflects their own views and values.


Under STV, as opposed to hybrid systems such as AMS, all MPs are elected on the same basis, thus lessening the chances of there being animosity between them.


There are no safe seats under STV, meaning candidates cannot be complacent and parties must campaign everywhere, and not just in marginal seats.


When voters have the ability to rank candidates, the most disliked candidate cannot win, as they are unlikely to pick up second-, third- and lower-preference votes.


By encouraging candidates to seek first-, as well as lower-preference votes, the efficacy of negative campaigning is greatly diminished.


There is no need for tactical voting.


There is a more sophisticated link between a constituency and its representative. Not only is there more incentive to campaign and work on a more personal and local level, but also, the constituencies are likely to be more sensible reflections of where community feeling lies. For example, there is more of an attachment to the City of Leeds or the City of Manchester, than there is to, say, Leeds North East or Manchester Withington, whose boundaries have a habit of changing fairly regularly anyway.


Further information

How to conduct an STV election

Voting Systems

Proportional Representation Mixed Systems Majoritarian Systems
More representative as seats are distributed according to vote share. Combines the features of majoritarian-style systems and Proportional Representation. Systems that are highly disproportional.
Single Transferable Vote Additional Member System First Past the Post
Party List PR Alternative Vote Plus Alternative Vote
    Borda Count
    Block Vote
    Limited Vote
    Supplementary Vote
    Two-Round System