This article explores the dynamics behind the development of British credit unions in the the 1960s. It explains how members of West Indian and Irish immigrant communities mobilised to overcome both financial exclusion and the high charges that were imposed on them by mainstream financial institutions. The article explains the global movement of people and ideas that created these credit unions. Particular attention is paid to a number of social justice activists within the Catholic Church who were very important in their transmission. British credit unions were established on a small-is-beautiful ideology, with modest memberships enabling high levels of social connectedness between the individuals involved. These credit unions were often viewed not just as a financial institution, but also as a powerful tool for self-empowerment and community building. The article explores the subsequent tensions within the British credit union movement that emerged between modernisers, who wanted them to expand into sizeable institutions, and traditionalists who valued the original philosophy of the British credit union movement.