The seeds from newer, varieties of determinate lupin grown in the UK are potentially a useful source of protein to livestock. Also, their ability to be cultivated in a temperate climate may afford the opportunity to reduce the dependence on imported protein sources such as soya bean meal. There is also currently interest in assessing the potential for harvesting whole-crop forage lupin (WCFL) as a high-protein forage crop for ruminant animals. The aim of the present study was to examine the nutritional value of WCFL samples harvested at different stages of maturity.