High profile cases of exploitative labour practices have increased concerns over agricultural working conditions. However, it is unclear to what extent the public is willing to trade-off fair working conditions for higher prices. We implement a large-scale survey to uncover consumer preferences for a food labeling system that certifies fair working conditions for the workers employed in agricultural production. We test for several methodological issues * We'd like to thank the Editor and two anonymous reviewers for their constructive comments. Drichoutis, Vassilopoulos and Lusk acknowledge funding by the John S. Latsis Public Benefit Foundation. The sole responsibility for the paper's content lies with its authors. We also acknowledge the help of several people: Sotiria Alexandri, Nikos Bochoridis, Christina Chliaoutaki, Froso Gkika, Almarina Gkramozi, Eirini Kostoula, Maria Michalopoulou, Alexandra Papadopoulou, Eleftheria Papamichali, Sofia 1 with respect to value elicitation and predictions of reference dependent theory. With our most conservative estimates, we find that consumers are willing to pay an average premium of 53 cents per 500 gr, 95% CI [43.9, 62.3], for strawberries with fair labour certification.