Evidence on the performance of market-based sanitation (MBS) interventions is needed to support renewed focus on using them to deliver sanitation services at scale. We conducted a comprehensive review of WASH grant-funding since 1980 to identify household sanitation supply projects using an MBS approach, assessed project characteristics and outcomes (population impacted), and reviewed project strategies against three key factors for scaling MBS (customer and business finance; availability and viability of local entrepreneurs; appropriate toilet product and business models). For a subset with higher outcomes, we assessed project strategies more fully against nine MBS strategies considered good practice, and the programme’s ability to leverage household investment. Of 103 sanitation supply projects in eight global databases, 49 qualified as MBS and occurred in 22 countries across sub-Saharan Africa, South/Southeast Asia, and Latin America. Cumulatively, 27.6 million people, nearly all rural, gained access to basic sanitation via markets across these projects. ‘Large-scale’ MBS projects exceeding 50,000 people gaining basic sanitation (n = 27) compared with those that did not (n = 22) were longer and significantly more likely to address all three key factors (74 per cent vs. 41 per cent; p = 0.019), but on average applied only six of nine good practice strategies. Outcomes and programme leverage were higher in South/Southeast Asia than in sub-Saharan Africa. However, African projects tended to have shorter duration, fewer reached ‘large-scale’, and rarely employed a sales and marketing strategy. We discuss implications for improving the design and performance of MBS interventions globally and particularly in sub-Saharan Africa.