The majority bonus system (MBS) is a form of semi-proportional representation used in some European countries. Its feature is a majority bonus which gives extra seats or representation in an elected body to the party or to the joined parties with the most votes with the aim of providing government stability.

It is currently used in Greece[1],San Marino and Armenia, and formerly in Italy from 2006 to 2013. In Argentina, it is used in the Chamber of Deputies of the Province of Santa Fe, Chubut, and Entre Ríos.


Benito Mussolini was the first politician to enact a law to give automatic seats to the winning party and ensured his victory in the 1924 Italian general election. A modified version of the system was reintroduced for the 1953 Italian general election, in which any parliamentary coalition winning an absolute majority of votes would be awarded two-thirds of the seats in Parliament. The Christian Democracy-led coalition fell narrowly short of this majority in the election, and the system was abolished before the 1958 election. The majority bonus system was used in Italian local elections in the 1950s and was reintroduced for local elections in 1993 and national ones in 2006 to replace the scorporo mixed system. In the 2013 Italian general election, the Democratic Party won 292 seats in the House using its 8,644,523 votes and so needed 29,604 preferences to obtain a seat. Its major opponent, The People of Freedom, won 97 seats with 7,332,972 votes and so needed 75,597 votes for a single seat. Effectively, the system in use in Italy from 2006 until 2013, which assigned the jackpot regardless of the percentage of vote achieved by the largest party, was judged as unconstitutional by the Italian Constitutional Court.[2][3] After a proposed modification involving a run-off vote (between the top two alliances) was also struck down by the court, parallel voting was adopted for the 2018 Italian general election.[4]


It can be based on any form of mechanism used in party-list proportional representation, but a D'Hondt method is most likely, as it will rank seats in an exact order of vote share.

Basically, there are two different forms of majority bonus systems, with clearly different political results:


The majority bonus system was adopted by other European countries, especially Greece in 2004 and San Marino at the national level, and France for its regional and municipal elections.

Country Type of election Type of system Size of bonus/jackpot Proportional method Notes
Andorra local elections plurality bonus (non-compensatory) 50% Hare quota
Armenia national elections (legislative) majority jackpot (optional second round, compensatory) 54% Second round is held if no party reaches 54% of seats and no coalition government can be formed

If a party would receives more than 2/3 of seats, their share is capped at 2/3, all minority parties must have at least 1/3 of seats in total.

minority jackpot (compensatory) 33%
Greece national elections (legislative) plurality bonus 16.66%
San Marino national elections (legislative) plurality jackpot (compensatory) 55%


  1. ^ Greece used the system for its most recent election in 2019. A bill abolishing it passed in 2016 but said law will not take effect until the second election after it was passed, so the majority bonus system was used in the 2019 Greek legislative election before being abolished officially. This change was later undone however (albeit modifying the original system slightly), so the election after the next one (two election cycles from now) will return to using the majority bonus.
  2. ^ Unconstitutionality sentence by the Italian Constitutional Court
  3. ^ The ruling awaited in Palace of Consulta after the public hearing on 3 December 2013 could cause an earthquake the Italian public scene, changing some of coordinates that determine the behavior of politicians and the electorate: Buonomo, Giampiero (2013). "La legge elettorale alla prova di costituzionalità". L'Ago e Il Filo Edizione Online. Archived from the original on 2012-08-01. Retrieved 2016-04-10.
  4. ^ Marco Bertacche (March 2, 2018). "How Italy's New Electoral System Works". Bloomberg Politics.

Caciagli, Mario; Alan S. Zuckerman; Istituto Carlo Cattaneo (2001). Italian Politics: Emerging Themes and Institutional Responses. Berghahn Books. pp. 87–89.