The United Kingdom is one of the major destination of immigrants and approximately 50% of the UK immigrant population reside in London. This immigrant concentration has been linked to the city’s political, economic and administrative relevance globally and to the UK in particular. This paper presents empirical evidence that migration policy may also play a significant role in the locational choices and residential pattern of UK immigrants. A conceptual link is developed on the premise that migration policy plays a key role in creating and sustaining migration waves and by extension, the socio-economic, socio-cultural and demographic composition of immigrants which are also key factors in individuals’ locational choices and residential patterns. Using rigorous quasi-experimental techniques namely Regression Discontinuity Design (RDD) and Difference-in-Difference (D-in-D) style approaches, this research examines the impact of the 2004 accession of 10 new countries to the EU (EU A10) and the Immigration Act of 1971 on the concentration of immigrants in London as well as the general residential pattern of UK immigrants. The results reveal that EU A10 immigrants that immigrated to the UK after the 2004 migration liberalisation (post-EU A10 immigrants) have a 20% lower likelihood of residing in London and are more spread out to other regions, compared to the pre-EU A10 immigrants who have a higher concentration in London. The results also reveal that Commonwealth immigrants that immigrated after the introduction of new immigration restrictions in 1972 have a 10% higher likelihood of residing in London compared to Commonwealth immigrants that immigrated before 1972. These results provide new insight on the potential link between migration policy, locational choices and residential patterns of immigrants.