We define as a “final poll” one that conducted at least some of its fieldwork on or after the Monday before the election.

Scottish Parliament

Voters were given two ballot papers – one for their local constituency MSP, the other for a party list. Five final polls were conducted and their estimates of both the constituency and list vote are shown below. The tables also compare the average of the polls with the eventual outcome.

Constituency Vote

The average estimate of the five polls is within a point of the final outcome for all of the parties, making it a very creditable overall performance.

List Vote

The estimates of the list vote were slightly less accurate, with most polls underestimating SNP support and overestimating that of the Greens, but otherwise the average estimate was again no more than a point adrift of the final outcome.

The figures for two other polling companies whose last poll was completed before the Monday before polling day are shown below.

Constituency Vote

List Vote

Welsh Senedd

Voters were again presented with both a constituency and a list ballot paper. Two final polls of voting intentions were conducted.

Constituency Vote

List Vote

While very close for Plaid Cymru, the Conservatives and the Greens, both polls underestimated the level of Labour and Liberal Democrat support, and overestimated that for Others on the constituency ballot and the Abolish the Welsh Assembly Party in particular on the list.

London Mayor

Four final polls of the contest to be Mayor of London were conducted. The table shows their estimate of the first preference vote.

These polls were less accurate than those in Scotland and Wales. Although the average figure for the Greens was almost spot on, as was the estimate for combined tally of minor parties and independents, the polls overestimated the Labour and Liberal Democrat vote, and heavily underestimated the Conservatives.

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