Online food delivery (OFD) services offer a variety of food options and convenient ways of consuming meals; however, contaminated delivery packaging can gradually cause serious environmental problems owing to its low recycling value. This study explores the factors that drive (un)sustainable OFD consumption and how information-evoked emotions can induce pro-environmental OFD spillover effects. After observations and interviews, an online survey was developed and data was collected in two phases. The findings showed that family and friend norms exerted direct effects on sustainable OFD behaviors of consumers. High-cost pro-environmental habits were positively related to sustainable OFD intentions while low-cost pro-environmental habits were negatively associated. Only internal attribution-dependent emotions strongly predicted pro-environmental OFD spillover effects, especially when consumers attributed responsibility to themselves. To reduce OFD pollution, governments should create pro-environmental educational programs, design options compatible with consumers’ values, establish injunctive norms for OFD consumption, and sanction unsustainable OFD practices.