In the previous municipal elections, local political parties won by far most votes and seats. Nationally, all local political parties won 28% of the votes and a third of municipal council seats. Local parties have seen a steady rise since the 1990s. In 2018, Vlieland will be the only municipality in which no national political parties will contest the election.
The Party for Freedom (PVV), which had previously only participated in The Hague and Almere, initially planned to expand to a total of sixty municipalities, but has only been able to find suitable candidates in thirty, including Rotterdam. 50PLUS will expand to twenty municipalities, while the Party for the Animals (PvdD) will contest fifteen elections. Two new national political parties will make their entrance to municipal politics. Denk will contest the elections in fourteen municipalities, while the Forum for Democracy will only contest in Amsterdam. Additionally, the latter has endorsed the local party Livable Rotterdam.
45 municipalities did not have elections on 21 March due to mergers.
Municipal councils are elected using party-list proportional representation. The number of seats depends on the population of the municipality, ranging from nine seats for municipalities with a population below 3,000, to 45 seats for municipalities with a population over 200,000.
After the 2018 municipal elections, the GroenLinks held the largest share of seats on the municipal council, though not enough to hold a majority. As no party held a majority, a left-leaning governing coalition was formed between GroenLinks, D66, the Labour Party, and the Socialist Party, which together hold 26 of the city's 45 council seats.
The new city council elected Femke Halsema, a member of the GroenLinks, to be the mayor of Amsterdam. Halsema is the first women to be elected mayor of Amsterdam, as well as the first member of the GroenLinks to take that position.