The first Balkan flag to be the subject of an in-depth study by the CNR is the Bulgarian flag. It stands out for the organisation of its flows and for having the cheapest labour in Europe. Nearly half of the flag's international activity consists of transport between third countries in the west of the EU. Vehicles operating so far away rarely return to Bulgaria, and air shuttles are used to send the best-paid drivers home to rest. Coming from a country where the minimum wage (€214/month) is lower than that of the industrial regions of eastern China, Bulgarian drivers have maximum productivity, at least 140,000 km per year, boosted by mileage bonuses. However, their remuneration remains at the lowest level. It consists of 75% in travel allowances, on which social security contributions and income tax are not payable. This leads to an apparent employer contribution rate of 4 %.

The 2016 study on Bulgarian TRM provides all the details on this unusual flag. It is supplemented by a summary that includes comparisons with France.