The overwhelming majority of farmed fish produced throughout the world are killed with little or no consideration for their welfare. Fasting periods can be excessive, transport stressful and killing inhumane. At the time of writing, the salmon industry is the only sector in which consideration of the welfare of the fish at slaughter has resulted in significant improvements throughout most of the industry. There are signs of interest in the use of more humane slaughter methods for some other fish species. This is mostly initiated by the demand for higher standards from European fish retailers. For most species, the humane killing options are limited to percussive stunning and electrical stunning. However, even these methods can have a poor welfare outcome if insufficient consideration is given to the needs of the fish or if the equipment has not been properly designed. The use of food-grade anaesthetics to assist with the harvest has significant potential for improving welfare and their wider use should be investigated further.