Using a bilateral trade equation derived from a monopolistic competition model, we investigated market access reciprocity in food trade among the US, Canada, the EU and Japan. We explore country and industry-specific market access asymmetry through the border effect approach, re-challenging the underlying main explanations. Our findings reveal marked asymmetry in reciprocal border effect, both across countries and industries. Policy trade barriers, firstly in the forms of NTBs, the degree of product differentiation and ‘home bias’ in preferences, are all important factors in explaining levels in border effects. However, asymmetry in border effects are explained especially by trade policies. Alessandro Olper is associate professor in the Department of Agricultural, Food and Environmental Economics at University of Milano. Valentina Raimondi is researcher in the Department of Agricultural, Food and Environmental Economics at University of Milano.