Informal cross-border trade networks are critical to regional integration in East African Community (EAC), with Tanzania playing a significant role as part of the Economic Community of West African States (ECOWAS). The research employed participant observation and semi-structured interviews to gather data from traders in Tanzania’s border regions. Ethnographic methods were chosen for their ability to capture nuanced social dynamics within the context of informal economies. Participants reported that over 70% of cross-border trade is conducted through unofficial channels, highlighting the prevalence of shadow markets despite formal regulatory efforts. This study underscores the importance of integrating informal sectors into official development strategies to enhance regional economic integration and inclusivity. Policy recommendations include fostering dialogue between government agencies and local traders to develop sustainable cross-border trade regulations that respect cultural practices and socio-economic realities.