Apportionment in the European Parliament

The apportionment of seats within the European Parliament to each member state of the European Union is set out by the EU treaties. The apportionment of seats is not proportional to each state's population, nor does it reflect any particular mathematical formula; however, it is stated in the treaties that distribution of seats should be "degressively proportional" to the population of the member states. The process can be compared to the composition of the electoral college used to elect the President of the United States of America in that, pro rata, the smaller state received more places in the electoral college than the more populous states.

As of the 2014 parliamentary election the number of MEPs is 751 — 750 MEPs and a president — this being the maximum number allowed by the Lisbon Treaty.

When the Parliament was established in the 1950s as the 78 member "Common Assembly of the European Coal and Steel Community" the smaller states (Belgium, Luxembourg and the Netherlands) were concerned about being underrepresented and hence they were granted more seats than their population would have allowed. Membership increased to 142 with the Assembly expanded to cover the Economic and Atomic Energy Communities.

It then grew further with each enlargement. Membership reached 626 in 1995 with the Treaty of Amsterdam setting a limit of 700. The Treaty of Nice increased this to 732 and set out the future distribution for up to 27 states. In 2007 Romania and Bulgaria joined with 35 and 18 members respectively temporarily pushing the number of members over the ceiling to 785. In 2009 the number of members decreased to 736.

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Wikipedia