Refugee sites throughout the world are loci of economic activity, including small enterprises, but limited information exists on these. We advance knowledge by collecting and analysing data on 326 enterprises operating inside and outside Rohingya settlements in southeastern Bangladesh. We find the following: refugees have access to a diverse array of active businesses; Bangladeshis and Rohingya both operate businesses and the two communities interact through transactions in local goods, services, inputs, and labour markets; lending plays an important role in sustaining these economies, as approximately 50 per cent of transactions are on credit; Rohingya-run enterprises face greater challenges than their local counterparts: their businesses are smaller and less profitable, and refugee workers are paid lower wages than local workers; and about half of the difference in performance between Rohingya and Bangladeshis can be explained by levels of start-up capital, scale, location, and education.