“U.K. firms may be allowed to demand proof that customers do not have coronavirus under options being considered to help businesses reopen after the pandemic.”
UK is considering allowing a substitution of a Covid-19 test result for a vaccine passport. In the UK, such tests are free – albeit, the tests when used for asymptomatic screening have a false positive problem that puts you at risk of quarantine each time you get tested. In the U.S. tests can cost up to $125 each (worst case when done at an airport).