Background: In May 2020 England implemented a ‘soft’ opt-out system of consent to organ donation on the assumption that switching the default to one more closely aligned with the preferences of citizens would make organ donation easier. Methods: A mixed-methods evaluation comprising: review of Parliamentary debates and feedback from legislators; surveys and interviews with healthcare professionals; analyses of representative public attitude surveys and public responses to media campaigns; interviews with family members approached about organ donation and the public; and analysis of donor audit data (e.g. consent rates), informed by input from a lay (public) perspective. Results: Implementing a ‘soft’ opt-out system into a well-established and complex opt-in system has been challenging. Consent forms, procedures and audits have become more complicated. Professionals frequently have to move between scenarios with families where opt-out applies, and others where family consent (opt-in) is still required. Bereaved families have no idea when this is required and continue to believe they are the decision makers. There is an (increasing) mismatch between establishing one’s wishes on the organ donor register and what the family are asked after death by staff. Support for organ donation continues to vary between subgroups of the population. The opt-out system appears to have had little impact so far on these differences. Nonetheless, implementation created a context for mis/disinformation to spread, especially among minority ethnic and faith groups. Disruptions from COVID-19 mean any impact of the law change on consent rates remain unclear. Conclusions: COVID-19 has hampered the ability to identify the effectiveness of the law change. At the same time, the legacy of informed consent has made it difficult to adapt fully to the opt-out system. This has prevented the principle behind the Act that everybody is a potential donor being realised in practice. Rather than presuming that the opt-out system will work as intended, it is likely to be more effective to improve the organ donation system in other ways.