Belgium was recently included in the list of countries whose nationals are now allowed to enter Vietnam on the basis of an e-visa. That decision was approved by the Vietnamese government in the form of a decree (No 17/2019 / NĐ-CP). Although it officially went into effect on 01/02/2019 (and runs until 01/02/2021), it was only implemented on 25/02/2019.
Visa applicants must register on the website https://evisa.xuatnhapcanh.gov.vn/ to fill in the required information. The payment of 25 USD has to be done online too. According to the information from that website, the application is processed within 3 working days. You must print the visa to enter Vietnam.
E-visas are limited to one entry and valid for a maximum duration of 30 days. The destination is not limited to tourism alone; Business people can also use it. Only visitors in the framework of an official visit, members of the diplomatic corps, their families and their guests, still have to follow the old process. The visa with a view to long stay must also be applied for via the traditional process.
For further questions we advise you to contact the Vietnamese authorities.