There is a growing demand in the last years for farm-level sustainability data reflected in various initiatives from farmers, science and food or related industries. The broad aim to develop viable food production systems, through supporting the sustainable management of natural resources and climate action and to strive for more balanced territorial development are core values within the EU and are reflected in the changing Common Agricultural Policy (CAP). The CAP is one of the key drives of agricultural practice across the EU, it has become more oriented towards the concepts of sustainability reflecting these higher order objectives. The EU operates a farm-level monitoring system, the Farm Accountancy Data Network (FADN), which acts as a check to establish if such successful change is being achieved, currently the primary focus is on the economic dimension of sustainability. This article uses an FADN farm sample for which both FADN and additional sustainability data were available form a data collection carried out by the EU-project FLINT. In particular, we compare the relationship between input intensity, efficiency and sustainability. Sustainability performance of the farms is compared by applying sustainability thresholds as identified in a literature survey. The farms were grouped according to their degree of efficiency and sustainability and possible relationships with farm characteristics are analysed. Based on farm benchmarking, around one half of the farms was observed to be neither efficient nor sustainable, while 15% met our criteria for being classified as efficient and sustainable. The results of our study are not representative but illustrative and can be a starting point for further analyses in this field.