National apportionment of MP seats in the Riksdag whole country participates in the distribution of seats. However, a party that has received at least twelve per cent of the votes in a constituency participates in the distribution of the fixed constituency seats in that constituency. National apportionment of MP seats in the Riksdag The electoral system in Sweden is proportional. Of the 349 seats in the national diet, the unicameral "Riksdag", 310 are fixed constituency seats () allocated to constituencies in relation to the number of people entitled to vote in each constituency (). The remaining 39 leveling seats () are used to correct the deviations from proportional
Riksdag members of the Riksdag are elected in the general elections held every four years. All Swedish citizens who turn 18 years old no later than on the day of the election are eligible to vote in and stand for elections. A minimum of 4% of the national vote is required for a party to enter the Riksdag, alternatively 12% or more within a constituency. Substitutes for each deputy are elected at the same time as each election, so by-elections are rare. In the event of a snap election, the newly elected members merely serve the remainder of the four-year term.