•A significant negative relationship exists between age and food waste.•This is caused mainly by younger generations’ lack food management skills.•Younger generations are more likely to make impulsive purchases.•Interventions should focus on leftover use, fridge/freezer management and storing. There are generational differences in beliefs, attitudes, and behaviours with respect to food consumption and waste in households. Understanding these generational differences is necessary to be able to effectively combat household food waste. However, there is a deficit in studies that focus on these differences. To address this gap, we analysed survey results from 2187 households and interviews with 16 international experts to understand how food management skills and food waste behaviours are influenced by various generational groups. Findings support a significant negative relationship between age and food waste, that is, younger generations tend to waste more food. Increase in young consumers food waste is caused by lack of food management skills in the areas of shopping, storing, and cooking with leftovers. To encourage changes which support reducing food waste, it is recommended the messages targeting young consumers be communicated via combinations of intergenerational storytelling, web and smart phone-based Apps, and videos suitable for sharing on social media.