This paper examines the causal effects of online food delivery (OFD) platforms on household food security in the context of a developing country, Indonesia. We construct food security data from households’ consumption surveys from 2012 to 2022 and merged it with a novel dataset on OFD platform penetration across districts, compiled through a combination of internet scraping and machine learning. Utilizing a contemporary event-study estimator to analyze the impact, our findings indicate that the expansion of OFD services enhances food security at the district level, with a more pronounced effect in rural areas, among younger households, and male-led households. We also show that this impact is likely driven by increased competition in the food market.