All travelers must have been inoculated with one of the vaccines that have received the green light from European Medicines Agency (EMA) or World Health Organization (WHO) at least 14 days before their trip to the EU.
Those whose vaccination date is older than nine months must receive a booster dose in order to be permitted entry.
The EU has so far authorized vaccines produced by Pfizer-BionTech, Moderna, AstraZeneca and Johnson & Johnson. In addition to these shots, the WHO has also approved the vaccines produced by Chinese makers Sinopharm and Sinovac and Indian company Bharat Biotech.
For people inoculated with shots not approved in EU, its member states could also require a negative PCR test done 72 hours before departure and could apply additional measures like quarantine or isolation.
Until now, most EU countries have not admitted people from outside the bloc travelling for non-essential reasons, including tourism.
Vietnam has resumed commercial flights to 20 of 28 countries and territories that it operated direct flights to before the pandemic, including Frankfurt, London and Paris.
From March 15, Vietnam will fully reopen inbound and outbound tourism.