As the current neoliberal economic system, based on money and competition, is failing, the commons economy appears as a possible new arrangement to occupy its place. Half of humankind live in urban areas, a trend that will increase in the next 15 years – specially the growth of megacities. Brazil has two of them – São Paulo and Rio de Janeiro – where urban commons initiatives are flourishing, despite their lack of connection and visibility. This article explores the need for mapping, integration and creation of a governance structure to support and stimulate the urban commons in megacities, by using São Paulo as a case study. The scale, diversity and challenges offered by this type of environment can enrich and evolve the knowledge on the commons economy.