In a proportional representation system, a party receives the same proportion of seats as the proportion of second votes it receives. This means that if a party receives 14 percent of the votes, it is entitled to 14 percent of the seats in parliament. How fractional results are handled is determined in advance. Votes for parties that receive less than five percent of the vote are not taken into account in the distribution of seats.

In elections to the Bundestag or the House of Representatives, a mixed-member proportional representation system is used. This means that proportional representation (second vote) is combined with the election of a direct candidate in each electoral district (first vote). As a result, the overall distribution of parties in parliament can be determined while voters also have more influence on the personal composition of parliament.