Alternative Vote

The Alternative Vote (AV), also called instant-runoff voting (IRV) in the United States and ranked-choice voting in some jurisdictions, is a majoritarian electoral system used to elect a single candidate per district. Instead of marking one preference, voters rank candidates in order: 1, 2, 3, and so on. If a candidate secures more than 50% of first-preference votes, they win outright. If no one clears that threshold, the candidate with the fewest first preferences is eliminated and their ballots are redistributed according to the next preference marked. The process repeats until a candidate holds a majority of the remaining valid votes.

AV is the long-standing system for elections to Australia's House of Representatives, where it has been used federally since 1918. It is also used for presidential elections in Ireland and for the Irish presidency and certain by-elections, as well as for mayoral and legislative races in several U.S. cities and, since 2020, statewide federal elections in Maine.

Proponents argue AV reduces wasted votes, discourages strategic "lesser evil" voting, and forces candidates to appeal beyond their core base because second preferences matter. Critics contend it can still produce non-proportional legislatures, is more complex to administer and count, and may not always elect the Condorcet winner (the candidate who would beat every rival in head-to-head matchups).

AV should be distinguished from related systems:

• Two-round system (e.g., French presidential elections): a separate runoff is held days or weeks later.
• Single Transferable Vote (STV): applies similar preference logic but in multi-member districts, producing proportional results.
• Supplementary Vote: voters mark only two preferences, used historically for some UK mayoral races.

The United Kingdom held a national referendum on adopting AV for House of Commons elections on 5 May 2011; voters rejected the change by roughly 68% to 32%.