As of 3 June, self-isolation is not required for Latvian nationals, permanent residents, and foreigners who have not visited any "unsafe" countries in the last 14 days - i.e., countries where the 14-day cumulative number of Covid-19 cases exceeds 16 people per 100,000 inhabitants - or countries outside of the EU, EEA, or Switzerland. The list of countries is published on the website of the Centre for Disease Prevention and Control and is updated every Friday.
Self-isolation is also not required for Lithuanian or Estonian nationals transiting Latvia. However, if a person is arriving from a “safe” country by transiting through an “unsafe country” (for example, arriving from Norway via Sweden), the person must observe self-isolation; in order to avoid self-isolation, a different return route must be chosen.
Persons who had previously returned from "safe" countries and have been observing self-isolation are not required to carry on with it and are allowed to only follow the social distancing rules and other epidemiological instructions.
Persons arriving from "unsafe" countries - i.e., countries with a 14-day cumulative number of Covid-19 cases that exceeds 16 people per 100,000 inhabitants - as well as from countries outside of the EU, EEA, or Switzerland (see list here), must still observe self-isolation.
As of 1 July, mouth and nose coverings are not obligatory on public transport anymore. However, their use is recommended, especially for persons with signs of a respiratory disease (runny nose, cough). This does not apply to persons coming from countries abroad that have a high incidence of Covid-19: these persons are still required to use a mouth and nose covering on public transport when going to their residence to self-isolate.