Private sustainability standards are increasingly important in food trade with developing countries but the implications for smallholder farmers are still poorly understood. We analyze the implications of different coffee certification schemes in Ethiopia using cross-sectional survey data, and regression and propensity-score-matching techniques. We find that Rainforest Alliance (RA) and double Fairtrade-Organic (FT-Org) certification are associated with higher incomes and reduced poverty, mainly because of higher prices, Fairtrade (FT) certification hardly affects welfare; and Organic (Org) certification reduces incomes, mainly because of lower yields. Cooperative heterogeneity importantly shapes these results. Results imply that private standards may not always deliver what they promise to consumers.