When were internal tariffs removed within the European Economic Community?

The European Economic Community (EEC) successfully abolished all internal tariffs for both industrial and agricultural products by July 1968.123

While the Treaty of Rome established the framework for this customs union in 1957, the process was implemented in stages, with the first reduction of internal tariffs occurring in January 1959. By the middle of 1968, the member states had met their timetable for the removal of these trade barriers, significantly fostering economic integration among the participating nations.312