In the resurgence of elite sociology, formal (organizational-based network resources) and informal (non-organizational relations) social capital have garnered attention, but their mutual dynamics remain underexplored. This study addresses this gap, examining how both forms intersect among urban business elites, focusing on their roles on corporate boards, perceived as a front stage of power, and their places of residence, representing a back stage. Using multiple correspondence analysis, and thanks to social network analysis and geographic information systems, we examine the evolution of business elites (n=2164) in Basel, Geneva, and Zurich along the 20th century. Our findings identify two dominant elite fractions: the ‘heirs’ and the ‘established’. The heirs’ power is concentrated within a clearly defined spatial context especially through informal social capital, while the established derive their power from extensive possession of formal social capital. The varying presence of these two groups mirrors developments of Swiss capitalism in the 20th century.