self-isolate for the first 14 days after you arrive in the UK, the government will also use the information to check that you’re self-isolating.You may be fined up to £100 if you refuse to provide your contact details, or more if you break this rule more than once.
You also may not be allowed to enter the UK (unless you’re either British or a UK resident).Do not travel if you have coronavirus symptoms.If you develop coronavirus symptoms when you’re travelling to the UK, tell the crew or driver on your plane, ferry, train or bus.