Lagos, the leading African megacity, is a coastal city located in creeks and riparian environment. In all parts of the city, transactions in marginal lands-riparian or water-logged areas-are increasingly becoming more noticeable. However, while previous studies have focused upon normal land transactions, the dynamics of land uses in marginal regions remain largely unexplained. Information on the dynamics of informal land transactions in the marginal regions of Lagos city is important for urban sustainability. This study therefore interrogates the attributes, uses, values and drivers of marginal land in Lagos using generalized linear model (GLM). Findings show that the predominant land use in marginal areas of Lagos is residential, majority of the lands are less than full plot size, close to river channels and less accessible, and the mean price ranges from NGN 3,156,908 to NGN 4,052,158. The GLM estimations show that distance to river channels/lagoon and buyer's status have more significant influence on marginal land uses and values in Lagos. These findings have significant policy and practical implications for the city's land use and sustainability. For urban and environmental sustainability, there is need to stem transactions in coastal marginal environments of Lagos for their obvious implications for climate change, flooding, erosion, sea incursion, building collapse, natural parks and public spaces, river channels and urban greening.