We discuss whether and under what conditions people should be allowed to choose which COVID-19 vaccine to receive on the basis of personal ethical views. The problem arises primarily with regard to some religious groups’ concerns about the connection between certain COVID-19 vaccines and abortion. Vaccines currently approved in Western countries make use of foetal cell lines obtained from aborted foetuses either at the testing stage or at the development stage. The Catholic Church’s position is that, if there are alternatives, (...) Catholic people have a moral obligation to request the vaccine whose link with abortion is more remote, which at present means that they should refuse the Oxford/AstraZeneca vaccine. We argue that any consideration regarding free choice of the vaccine should apply to religious and non-religious claims alike, in order to avoid religion-based discrimination. However, we also argue that, in a context of limited availability, considering the significant differences in costs and effectiveness profile of the vaccines available, people should only be allowed to choose the preferred vaccine if: 1) this does not risk compromising vaccination strategies; and 2) they internalize any additional cost that their choice might entail. The State should only subsidize the vaccine that is more cost-effective for any demographic group from the point of view of public health strategies. (shrink)