In the 1870s and 1880s, well-to-do merchants in Ottoman Thrace and Macedonia acted as creditors for increasingly cash-strapped but market-oriented cultivators while modest merchants traded credit amongst themselves through personal loans and bills of exchange. Many of these transactions had by then become integrated into modern commercial law embodied in Ottoman codebooks such as the Commercial Procedures of 1861. The standardization of commercial law over the course of the nineteenth century had created a separate specialized field of knowledge that merchants, creditors, and legal professionals needed to come to terms with in order to accumulate capital and expand their market networks. With the establishment of the Régie Company — the monopoly-holder over tobacco sales and cigarette production from 1883 onwards — tobacco merchants were obligated to adhere to Régie policy for cultivating, transporting, and selling their tobacco. At least that was the theory. However, some merchants continued to mobilize resources and relationships in an effort to circumvent the stipulations of the Régie and continue benefitting extensively from the tobacco trade. Portfolio capitalism was conceptually born out of historiographical debates over the economic legacies of Mughal India. The originators of the term used it to dispel the alleged division between the commercial and political realms in early modern South Asia. In the very different context of the late Ottoman Empire, following decades of reform, Ottoman merchants were supposedly relegated to an apolitical status and the specialization of commercial law created distinct ‘legal’ professions. However, the historical examples analyzed in this paper demonstrate that this separation provided the most industrious tobacco merchants with a framework for confronting the Régie Company as a political force within the context of commercial law. In particular, a number of merchants maintained robust commercial portfolios in part thanks to their own legal expertise and their personal networks within the provincial administration. At the same time, legal experts could work in tandem with international financial bodies like the Régie or on behalf of the customs office to force merchants into submission and thereby advance the agenda of the Ottoman Empire’s international creditors and the policy goals of the Sublime Porte. By analyzing the commercial entrepreneurship and legal expertise of these merchants, this paper seeks to utilize portfolio capitalism to generate new understandings of political economy in late nineteenth-century Ottoman Thrace and Macedonia.