The COVID-19 pandemic has generated an imbalance between the clinical needs of the population and the effective availability of advanced life support (ALS) resources. Triage protocols have thus become necessary. Triage decisions in situations of scarce resources were not extraordinary in the pre-COVID-19 era; these protocols abounded in the context of organ transplantation. However, this prior experience was not considered during the COVID-19 outbreak in Spain. Lacking national guidance or public coordination, each hospital has been forced to put forth independent and autonomous triage protocols, most of which were, nonetheless, based on common ethical principles and clinical criteria. However, controversial, non-clinical criteria have also been defended by Spanish scientific societies and public institutions, including setting an age cut-off value for unilaterally withholding ALS, using ‘social utility’ criteria, prioritising healthcare professionals or using ‘first come, first served’ policies. This paper describes the most common triage criteria used in the Spanish context during the COVID-19 epidemic. We will highlight our missed opportunities by comparing these criteria to those used in organ transplantation protocols. The problems posed by subjective, non-clinical criteria will also be discussed. We hope that this critical review might be of use to countries at earlier stages of the epidemic while we learn from our mistakes.