While immigration has played a major role in public debate in the UK over the past twenty years, citizenship and naturalisation have received much less attention. Polling data have suggested that the UK public is broadly supportive of the idea of giving long-term migrants the opportunity to become UK citizens (British Future, 2020). The UK Home Office, in its 2019 Indicators of Integration Framework, described citizenship as an “important bedrock to the integration of any individual in a society” (Ndofor-Tah et al., 2019: 18). Indeed, there is some evidence that becoming a citizen has a positive impact on economic and social integration. For example, the OECD (2011) found that naturalisation was associated with labour market outcomes of many groups of foreign nationals in France, Germany, Sweden and the United States, particularly for the most disadvantaged. Studies from Switzerland and Germany have also shown positive social and economic impacts of naturalisation (Hainmueller et al., 2017; Gathmann & Keller, 2018; but see also Bartram, 2019); and that those who naturalise increase their attachment to British Identity (Bartram, 2021).