The estuarian and lagoon areas of southeast Benin are atypical lake territories where private property rights are hereditary from endogenous legal tradition. People live in stilt dwellings and are exclusively dedicated to free-to-access fishing. Consequently, an increasing number of fishers with low respect for the State’s general rules for sustainable fishing contribute to legal pluralism and the tragedy of the commons. Co-management of small-scale fisheries has been advocated to offer various benefits, including improved socio-ecological integration, shared sustainable livelihoods, and adherence to biodiversity objectives. This study aims to assess the factors that influence the willingness of small-scale fishers to adopt property rights co-management options in southeast Benin. The data were collected using the discrete choice experiment method. The results show that 44% of fishers are willing to adopt property rights co-management options. This willingness is determined by their involvement in the co-management committee, access to a subsidy and livelihood diversification options. These fishers are the oldest in the sample and primarily owners of Acadja, a traditional fishing tool made of bush and tree branches planted in the lake. Institutional agreements for co-management establishment, such as subsidies to support small-scale fishers’ livelihood diversification and capacity-building, must be set up to achieve co-management goals.