According to the Ministry of Foreign Affairs:
Romanian visa
Conditions regarding the entry of foreigners on the Romanian territory
CAREFUL! According to the provisions of Regulation (EU) no. 610/2013, starting with October 18, 2013, when calculating the right of residence for third-country nationals, a period of maximum 90 days in any period of 180 days is taken into account. You have the opportunity to calculate your right of residence by using the calculation system provided for this purpose by the European Commission.
