AbstractGenetically modified maize Bt11 × MIR162 × MIR604 × MON 89034 × 5307 × GA21 was developed by crossing to combine six single events: Bt11, MIR162, MIR604, MON 89034, 5307 and GA21, the GMO Panel previously assessed the 6 single maize events and 27 out of the 56 possible subcombinations and did not identify safety concerns. No new data on the single maize events or the assessed subcombinations were identified that could lead to modification of the original conclusions on their safety. The molecular characterisation, comparative analysis (agronomic, phenotypic and compositional characteristics) and the outcome of the toxicological, allergenicity and nutritional assessment indicate that the combination of the single maize events and of the newly expressed proteins in the six‐event stack maize does not give rise to food and feed safety and nutritional concerns. The GMO Panel concludes that six‐event stack maize, as described in this application, is as safe as the conventional counterpart and non‐GM maize varieties tested, and no post‐market monitoring of food/feed is considered necessary. In the case of accidental release of viable six‐event stack maize grains into the environment, this would not raise environmental safety concerns. The GMO Panel assessed the likelihood of interactions among the single events in 29 of the maize subcombinations not previously assessed and covered by the scope of this application and concludes that these are expected to be as safe as the single events, the previously assessed subcombinations and the six‐event stack maize. The post‐market environmental monitoring plan and reporting intervals are in line with the intended uses of maize Bt11 × MIR162 × MIR604 × MON 89034 × 5307 × GA21. The GMO Panel concludes that six‐event stack maize and the 30 subcombinations covered by the scope of the application are as safe as its conventional counterpart and the tested non‐GM maize varieties with respect to potential effects on human and animal health and the environment.