All forms of Brexit are bad for health, but some are worse than others. This paper builds on our 2017 analysis using the WHO health system building blocks framework to assess the likely effects of Brexit on the National Health Service (NHS) in the UK. We consider four possible scenarios as follows: a No-Deal Brexit under which the UK leaves the EU on March 29, 2019, without any formal agreement on the terms of withdrawal; a Withdrawal Agreement, as negotiated between the UK and EU and awaiting (possible) formal agreement, which provides a transition period until the end of December, 2020; the Northern Ireland Protocol's backstop coming into effect after the end of that period; or the Political Declaration on the Future Relationship between the UK and EU. Our analysis shows that a No-Deal Brexit is substantially worse for the NHS than a future involving the Withdrawal Agreement, which provides certainty and continuity in legal relations while the Political Declaration on the Future Relationship is negotiated and put into legal form. The Northern Ireland backstop has varying effects, with continuity in some areas, such as health products, but no continuity in others. The Political Declaration on the Future Relationship envisages a relationship that is centred around a free-trade agreement, in which wider health-related issues are largely absent. All forms of Brexit, however, involve negative consequences for the UK's leadership and governance of health, in both Europe and globally, with questions about the ability of parliament and other stakeholders to scrutinise and oversee government actions.