The Centers for Disease Control and Prevention (CDC) announced that effective December 28, 2020, American and foreign national air passengers arriving from the United Kingdom to the United States must test negative for coronavirus via the PCR or antigen test no more than seventy-two hours before departure from the UK to the US. The CDC notes that this order comes after UK public health authorities announced the discovery of a new variant of SARS-CoV-2 which may be up to seventy percent more transmissible than previously circulating variants. Numerous countries have announced new restrictions on UK travelers due to this new variant.

The CDC notes that this “additional testing requirement will fortify our protection of the American public to improve their health and safety and ensure responsible international travel.” In a statement, CDC explains: "Passengers are required to get a viral test (i.e., a test for current infection) within the 3 days before their flight from the U.K. to the U.S. departs, and provide written documentation of their laboratory test result (in hard copy or electronic) to the airline. Airlines must confirm the negative test result for all passengers before they board. If a passenger chooses not to take a test, the airline must deny boarding to the passenger."