Single Market Enlargement and Technical Barriers to Trade: Revisiting the Evidence

EU enlargements have given new EU member states access to the European Single Market. While tariff liberalisation was already completed at the time of enlargement, technical regulations were subject to different sectoral approaches, including harmonisation and mutual recognition. We employ a structural gravity model estimated using sectoral trade data from 1987 to 2020 to assess the trade effects of these measures. We find that trade expansion, particularly exports of the NMS to the incumbent EU members, has been stronger in the sectors covered either by the Old Approach (full harmonisation) or the New Approach (essential requirements) than in sectors covered by mutual recognition. The New Approach has been more effective when coupled with mutual recognition at the sector level than with either approach alone. Our results imply that the TBT harmonisation has had a heterogenous impact on different sectors (the most important for low-tech industries was the Old Approach, while for high-tech, it was the New Approach).