This chart includes estimates for one or more groups that are too small to be statistically reliable, interpret with caution.
View flagged groups- May 2015 - May 2015: 'Plaid Cymru', 'British National Party (BNP)', 'Other'
- Apr 2016 - May 2016: 'Plaid Cymru', 'Green Party', 'Other'
- May 2016 - Jun 2016: 'Plaid Cymru', 'Green Party', 'Other'
- Jun 2016 - Jul 2016: 'Plaid Cymru', 'Green Party', 'Other'
- Nov 2016 - Dec 2016: 'Plaid Cymru', 'Green Party', 'Other'
- Apr 2017 - May 2017: 'Plaid Cymru', 'Green Party', 'Other'
- May 2017 - Jun 2017: 'Plaid Cymru', 'Green Party', 'Other'
- Jun 2017 - Jun 2017: 'Scottish National Party (SNP)', 'Plaid Cymru', 'Green Party', 'Other'
- May 2018 - May 2018: 'Scottish National Party (SNP)', 'Plaid Cymru', 'United Kingdom Independence Party (UKIP)', 'Green Party', 'Other'
- Mar 2019 - Mar 2019: 'Scottish National Party (SNP)', 'Plaid Cymru', 'Green Party', 'Other'
- May 2019 - Jun 2019: 'Scottish National Party (SNP)', 'Plaid Cymru', 'United Kingdom Independence Party (UKIP)', 'Green Party', 'Other', 'Change UK- The Independent Group'
- Nov 2019 - Nov 2019: 'Scottish National Party (SNP)', 'Plaid Cymru', 'United Kingdom Independence Party (UKIP)', 'Green Party', 'Other', 'Brexit Party/Reform UK'
- Nov 2019 - Dec 2019: 'Scottish National Party (SNP)', 'Plaid Cymru', 'United Kingdom Independence Party (UKIP)', 'Green Party', 'Other'
- Jun 2020 - Jun 2020: 'Plaid Cymru', 'Other'
- May 2021 - May 2021: 'Plaid Cymru'
- Nov 2021 - Dec 2021: 'Plaid Cymru', 'Other'
- May 2022 - May 2022: 'Plaid Cymru'
- Dec 2022 - Dec 2022: 'Plaid Cymru', 'Other'
- May 2023 - May 2023: 'Plaid Cymru'
Source: British Election Study, 2015 - 2023 (N=310,234)