Group certification supports an increase in the diversity of sustainable agriculture network-rainforest alliance certified coffee producers in Brazil

•Group certification enhances the engagement of medium and small coffee producers.•Increased access is due to lower audit costs, although with same audit intensity.•Compliance with standards are equal for group and individually certified farms.•Producer profiles are diverse among group certified farmers.•There is high productivity among certified smallholders; marginalized remain excluded.

Socioenvironmental certification is a market-based mechanism aimed to foster sustainability of production systems. However, mainstream certification schemes in the agricultural sector have been adopted primarily by larger and more established producers, indicating an unequal distribution of social benefits. Group certification is often promoted as one alternative to increase accessibility for smaller producers, but there has been a lack of studies assessing this hypothesis. We assessed all coffee producers certified under the Sustainable Agriculture Network-Rainforest Alliance Certified system in Brazil in 2011, comprising 55 individual farms and 11 groups of individual producers. We found that group certification has increased access to small and medium size producers compared to certification for individually certified producers. There is diversity in the way producers are organized and in the profile of producers among and inside groups. However, the small producers participating in group certification are those with high productivity, suggesting that the most marginalized producers are still unable to access the certification system. Thus additional policy interventions will be necessary to promote more sustainable practices among the large numbers of marginalized coffee farmers in Brazil.