There are an unknown number of persons illegally resident in the UK. The Pew Research Centre estimate in 2017 was between 800,000-1,200,000 but this was a broad estimate. The reasons why these people live outside the mechanisms of the state are numerous and complex. Covid-19 represents an opportunity for regularisation. I propose an amnesty for all undocumented/illegally resident persons in the UK, they should be invited to come forward to submit their details so they can be added to the vaccination schedule to have their vaccine in turn as per the vaccine priority list. There is an incentive for the undocumented persons to come forward to get their vaccination in the short term and in the longer term potentially have their immigration status regularised. The policy could be sold to the portion of general public who generally look unfavourably on those illegally resident on the basis that it is a benefit for everyone in the UK that as many people as possible are vaccinated to improve the vaccine programme’s efficacy for all. Aligning this amnesty as a response to Covid-19 would make it clear that this amnesty is a one off. There is a Census taking place in 2021 so there could be some synergy there. The status given to the applicants will of course vary, some may gain a permanent right to live and work in some cases, in others perhaps time limited to one year after which they would become illegally resident again and further steps could be taken. In addition to improved vaccine coverage this proposal could: yield additional taxpayers, regularise the status of vulnerable persons, reduce crime, aid planning and in any event provide a once in a generation opportunity for a stock take of who actually resides in the UK.