Purpose: This paper aims to illustrate the application and effectiveness of a marketing programme co-designed by supply- and demand-side stakeholders to reduce consumer food waste in restaurants. Design/methodology/approach: This stakeholder-based marketing pilot study adopted the co-create, build and engage framework for programme design and implementation. Major stakeholders, interacting at the point-of-sale, participated in a series of focus groups, interviews and co-design. The research process informed the marketing mix, which aimed to provide value for all parties. The four-week pilot programme was delivered in a non-buffet-style commercial restaurant chain for 10 months. The amount of consumer food leftovers was measured and compared with pre-programme baseline data to evaluate programme effectiveness. Findings: The results show that the marketing mix co-designed by restaurant stakeholders and consumers effectively reduced food waste by almost half in the pilot period. The profitability of the pilot restaurant increased as food costs decreased. Research limitations/implications: This research demonstrates how working with stakeholders from both the supply and demand sides can identify motivations and barriers. Insights gained in the research phase can inform the delivery of a marketing mix that reduces consumer food waste. This study demonstrates the marketing research, design, implementation and evaluation process for a marketing programme that reduced consumer food waste. Practical implications: To effectively reduce consumer food waste, practitioners should not only focus on changing consumers’ behaviour. Co-designing solutions with food service stakeholders to address business and operation challenges is crucial to the attainment of a positive impact at the point-of-sale. Originality/value: This research shows how marketing changes behaviour in individuals and business entities, contributing to positive environmental impact through waste reduction in the commercial food service sector.