Khakbazan, M., Henry, R., Haung, J., Mohr, R., Peters, R., Fillmore, S., Rodd, V. and Mills, A. 2015. Economics of organically managed and conventional potato production systems in Atlantic Canada. Can. J. Plant Sci. 95: 161-174. A rotation study was initiated in 2007 in Prince Edward Island (PEI), Canada, to determine the economic effects of converting from conventional potato production to organically managed systems. Seven organically managed rotations, which used various crop combinations to help control pests and soil-borne diseases as well as maintain nutrient levels, were assessed for 2 yr before and 2 yr after organic certification requirements were met in 2009. Each rotation included potato as the main cash crop and at least one other cash crop in a 4-yr rotation and these rotations were compared to a 4-yr conventional rotation. Results indicated that without an organic price premium, significant net revenue losses are expected for most of the seven rotations because of lower yields and high costs. The rotation that included carrots (potato, carrots and mixed peas-oats grain as the cash crops) produced the highest net revenue amongst all rotations studied; however, carrot yield and the net revenue associated with it also showed the greatest variability among all the crops. Organically managed cash crops generated higher net revenues than the conventional potato system only if the average PEI organic price premium was applied. Conventional potato systems produced economic benefits similar to most of the organic rotations when a traditional potato-cereal-green manure rotation was evaluated. The comparison of seven possible rotations provides producers with options if growing organic potatoes.