The Tax Administration of France issued on 25 June 2014 guidelines for those workers who work on ships and aircraft in international traffic under the France-Portugal Income Tax Treaty of 1971.

Under provision of paragraph 3 of Article 16 of the treaty, income of those workers who work on ships or aircraft in international traffic will be taxable in both states, where their place of effective management is situated, and in the state in which they are resident. The state of residence of the worker should eliminate any double taxation.