The fate of nitrogen (N) fertiliser applied to bioenergy crops is a key issue to allow high biomass production while minimising environmental impacts due to N losses. The aim of this study was to follow the fate in the soil-plant system of N fertiliser applied to perennial (Miscanthus x giganteus and switchgrass), "semi-perennial" (fescue and alfalfa) and annual (sorghum and triticale) bioenergy crops. Crops received N-15-labelled fertiliser (urea ammonium nitrate solution) during 4 or 5 successive years on the same subplots, at a rate varying from 24 to 120 kg N ha(-1) yr(-1). Biomass production, N and N-15 removal at harvest were measured each year. The N-15 recovery in crop residues, non-harvested crop parts and soil was measured at the end of the N-15-labelling period. Perennial crops had higher biomass production but generally lower N-15 recovery in harvested biomass than other crops, particularly when harvested late (end of winter). At the end of the 4 or 5-year period, the proportion of N-15 recovered in harvested biomass was 13-34% for perennials, 23-38% for semi-perennials and 34-39% for annual crops. Perennial crops stored large amounts of N in their belowground organs; the mean N-15 recovery in these organs was 12%, corresponding to a N storage flux of 14 kg N ha(-1) yr(-1). The N-15 recovery in soil (including crop residues) was higher for perennials (average 36%) than semi-perennials (28%) and annual crops (19%), corresponding to a N immobilisation rate of 43,15 and 12 kg N ha(-1) yr(-1) respectively. The mean overall N-15 recovery in the soil-plant system was 69% in perennials, 61% in semi-perennials to 56% in annual crops, suggesting that important fertiliser losses occurred through volatilisation and denitrification. Perennial bioenergy crops had the better efficiency by storing fertiliser-N in soil organic matter and living belowground biomass used as N reserves for succeeding years. (C) 2016 Elsevier B.V. All rights reserved.