[2] Initial media coverage interprets the 2019 election results as a "green wave" marking a leftward shift of the Swiss electorate on the political spectrum.

[7] In contrast to Germany and Austria, the Swiss federal government has for decades been composed of representatives of the four largest parties as a matter of political practice (rather than constitutional design); it has long operated on a consensus-seeking model characterised by accommodation of competing interests and viewpoints, rather than imposition of the will of the majority over the opposition.

Switzerland's confederate structure and frequent initiatives and referendums pose additional constraints on what elected politicians are collectively able to accomplish.

For these reasons, the strong electoral gains of the two green parties do not have the same implications for coalition-government formation as they do in Austria following the 29 September 2019 parliamentary elections there, in which the Greens obtained their best results ever with 13.9% of the vote and 26 seats in a slightly smaller lower house of Parliament.

The cantons individually organise their elections for the Council of States, which all held on 20 October 2019,[8] with one exception.

[10] National Council seats are apportioned to the cantons based on their respective population size (which includes children and resident foreigners who do not have the right to vote).

In Jura and Neuchâtel the elections are held using proportional representation, whilst the other 24 use the majority system.

Other parties contesting in at least three cantons are: The chart below depicts opinion polls conducted for the 2019 Swiss federal election; trendlines are local regressions (LOESS).