Saving as many lives as possible while ensuring equity for vulnerable groups through access to triage resources has been the dominant position since the onset of the COVID-19 pandemic in 2020. However, the exact relationship between the principles of social justice and efficiency remains a controversial and unresolved issue. In this paper, we aim to systematically distinguish between different models of this relationship and show that conceptualizing social justice as a ‘moral side-constraint’ or adopting a ‘balancing approach’ that attempt to (...) reconcile social justice with efficiency inevitably lead to significant moral costs that require further justification. Based on this discussion, we propose a novel “threshold model” for trading-off moral costs. According to this model, the structural impact of triage must be considered in order to determine whether one opts for triage with the primary aim of efficiency or social justice. This contextualization further explains why, in some societies and circumstances, social justice can rightly be seen as the primary concern, while in other societies and circumstances, efficiency can be defended as the primary concern. (shrink)