How accurate the pollsters were

For every pollster: the average difference between its final poll and the result, how many elections that rests on, and the period those polls span.

A pollster with fewer than 3 scored elections is listed here with its figures and marked as such. Its average is shown for completeness, not as a verdict: an average over one or two elections says more about those elections than about the pollster.

Every election we hold a result for

• 2024 general election 2024-07-04
• 2019 general election 2019-12-12
• 2017 general election 2017-06-08
• 2015 general election 2015-05-07
• 2010 general election 2010-05-06
• 2005 general election 2005-05-05
• 2001 general election 2001-06-07
• 1997 general election 1997-05-01
• 1992 general election 1992-04-09
• 1987 general election 1987-06-11
• 1983 general election 1983-06-09
• 1979 general election 1979-05-03
• October 1974 general election 1974-10-10
• February 1974 general election 1974-02-28
• 1970 general election 1970-06-18
• 1966 general election 1966-03-31
• 1964 general election 1964-10-15
• 1959 general election 1959-10-08
• 1955 general election 1955-05-26
• 1951 general election 1951-10-25
• 1950 general election 1950-02-23
• 1945 general election 1945-07-05

How this is measured: for each past election we take each pollster’s last poll in the 30 days before polling day and compare it, party by party, with the result. The figure is the mean absolute difference across the parties that appear in both. Only parties the pollster actually reported are counted. A late shift in opinion is not the same thing as a polling error.