Update: On March 18, the Government of Latvia decided to include the United Kingdom and Switzerland on a list of exempt countries and to treat them the same as other EU countries. Therefore, the previously announced additional requirements for travellers to Latvia to take a second Covid-19 test upon arrival and, in the case of a positive test result, for travellers to have to self-isolate at a hotel, have been rescinded. Previous requirments remain in place with the recommendation to avoid travel that is not essential, take the PCR Covid-19 test at least 72 h before departure, register with the covidpass.lv and self-isolate at home for 10 days.
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As of March 17, in order to enter Latvia from third countries, including the United Kingdom, in addition to the existing entry requirements, travellers will have to take a second Covid-19 test. If the test result is negative, then 10 days of self isolation must be spent at home. If the test result is positive, then self isolation must be spent at a hotel. Travellers will have to cover the hotel stay costs themselves. These requirements are in effect pending further decisions.
Existing requirements already ask for proof of essential travel when leaving the United Kingdom, a Covid-19 PCR test (not older than 72 h before departure) and registration with covidpass.lv. It is still advised not to travel abroad without urgent need.