The article investigates the economic links between the Italian trading companies Brentano, Guaita and Bolongaro, which migrated to Frankfurt on Main before 1700, and the Dutch trading centre Amsterdam. In the eighteenth century they operated branches in both cities and purchased mainly Italian goods and colonial goods from Amsterdam. However, the Amsterdam branches soon grew beyond the role of pure purchasing offices for goods for the German market and became involved in the Amsterdam stacking business and intra-European maritime trade. As a result, the representatives in Amsterdam succeeded in raising the company owners to the upper class there, with the Dutch branches often splitting off from their German parent companies after 1750. The detailed case study analysis here provides an illustration of the great importance of West German foreign trade with the Netherlands when Amsterdam connected the German hinterland to the Atlantic world economy.