Informal cross-border trade plays a significant role in regional integration efforts within ECOWAS (Economic Community of West African States). The region is characterized by diverse economies and varying levels of development, which can complicate the implementation of formal integration strategies. The review synthesizes secondary data from published research articles, academic conferences, and policy documents. Qualitative analysis is employed to assess the thematic relevance of studies focusing on informal trade practices across ECOWAS member states. Informal cross-border trade represents approximately 20% of total regional commerce in some countries, indicating its substantial economic importance despite regulatory gaps. While informal trade contributes significantly to regional economic activity, it also poses challenges related to tax evasion and limited market accessibility for small-scale producers. Effective integration requires addressing these issues through targeted policy interventions. Policy makers should prioritise the development of standardised trading platforms and robust enforcement mechanisms to harness the full potential of cross-border informal trade within ECOWAS.