About Single Transferable Vote

Single Transferable Vote (STV) is a voting system for elections with more than one winner. It gives voters the chance to rank candidates in order of preference, and it helps ensure the final result reflects the group as a whole.

Why use STV?

• Reduces wasted votes
• Reflects diverse opinions fairly
• Encourages honest rankings
• No need for tactical voting

STV is used around the world in places like Ireland, Malta, Australia, and for many local and organizational elections.

How STV works

Here’s a step-by-step overview of how votes are counted:

1. Voters rank candidates in order of preference: 1st, 2nd, 3rd, etc.
2. A quota is calculated based on the number of votes and seats.
3. First-choice votes are counted. Anyone who reaches the quota is elected.
4. If a candidate has extra votes, their surplus is transferred to other candidates based on next preferences.
5. If no one reaches the quota, the candidate with the fewest votes is eliminated, and their votes are transferred.
6. This repeats until all seats are filled.

An example

Suppose you’re electing 3 people. Voters might rank the candidates like this:

1. Jamie
2. Alex
3. Taylor

If Jamie gets more votes than needed, their extra votes go to Alex. If Taylor has the fewest votes, they’re eliminated and their votes go to the next choice on those ballots.

How the quota works

We use the Droop Quota, which is:

For example, if there are 100 votes and 3 seats, the quota would be:

So any candidate with 26 or more votes is elected.

How we handle ties and transfers

Our app uses fractional vote transfers when redistributing surplus votes. In the case of a tie, we follow a consistent rule based on earliest rounds of elimination or a random tie-break if needed.

You can read the full details in our source code documentation.