We study the effects of Fair Trade (FT) certification of coffee on producers and households in Costa Rica. Examining the production dynamics of all Costa Rican coffee mills from 1999-2014, we find that when global coffee prices are lower and the FT guaranteed minimum price is binding, FT certification is associated with a higher sales price, greater sales, and more revenues. We also find that certification reduces the probability of a mill closing down and exiting the industry. Looking at households, we find that certification is associated with higher incomes for farm owners. Part of this is due to a transfer of incomes from intermediaries whose incomes decrease due to FT. We find no effect of FT on unskilled workers, who are the more disadvantaged group within the coffee sector.