Opinion polling for the next Icelandic parliamentary election

In the run up to the next Icelandic parliamentary election, various organisations carry out opinion polling to gauge voting intention in Iceland during the term of the Althing. This article lists the results of such polls.
The date range for these opinion polls is from the previous election, held on 28 October 2017, to the present day. The elections are to be held on or before 23 October 2021.
Polls are listed in reverse chronological order, showing the most recent first and using the dates when the survey fieldwork was done, as opposed to the date of publication. Where the fieldwork dates are unknown, the date of publication is given instead. The highest figure in each polling survey is displayed with its background shaded in the leading party's colour. If a tie ensues, this is applied to the highest figures. When a poll has no information on a certain party, that party is instead marked by a dash (–).
Graphical summary.
D = Independence Party, V = Left-Green Movement, S = Social Democratic Alliance, M = Centre Party, B = Progressive Party, P = Pirate Party, F = People's Party, C = Reform Party, J = Socialist Party.