英国国家经济和社会研究所-英国脱欧与非关税壁垒：对英国商业投资和生产力的影响（英）

BREXIT AND NON-TARIFF BARRIERS: EFFECTS ON UK BUSINESS INVESTMENT AND PRODUCTIVITY NIESR Discussion Paper No. 572 August 2025 Ahmet Kara1 Hailey Low Stephen Millard1 1 National Institute of Economic and Social Research About the National Institute of Economic and Social Research The National Institute of Economic and Social Research is Britain's longest established independent research institute, founded in 1938. The vision of our founders was to carry out research to improve understanding of the economic and social forces that affect people’s lives, and the ways in which policy can bring about change. Over eighty years later, this remains central to NIESR’s ethos. We continue to apply our expertise in both quantitative and qualitative methods and our understanding of economic and social issues to current debates and to influence policy. The Institute is independent of all party-political interests. National Institute of Economic and Social Research 2 Dean Trench St London SW1P 3HE T: +44 (0)20 7222 7665 E: enquiries@niesr.ac.uk www.niesr.ac.uk Registered charity no. 306083 This paper was first published in August 2025 Competing Interest Statement: The views expressed in this paper are based on research and are not attributed to the organizations to which the researchers are affiliated. There are no conflicts of interest. The usual disclaimer applies. © National Institute of Economic and Social Research 20251 Brexit and Non-Tariff Barriers: Effects on UK Business Investment and Productivity Ahmet Kaya*, Hailey Low and Stephen Millard1 Abstract This paper investigates the macroeconomic impacts of increased non-tariff trade costs resulting from Brexit on UK business investment and productivity growth. We develop a three-country Dynamic Stochastic General Equilibrium model that accounts for differences in country sizes as well as tariff and non-tariff trade costs. Our results suggest that the increased trade costs resulting from Brexit led to a sharp decline in trade between the United Kingdom and the European Union, with imports decreasing by 23.7 per cent and exports by 18.6 per cent. Following an initial decline of around 2.5 per cent, business investment gradually recovers but ultimately remains 1.2 per cent lower in the long term. We further provide simulations of the same shock using the National Institute Global Econometric Model, NiGEM, which suggests comparable macroeconomic effects. The long-term impact on per capita output is estimated at 1.2 per cent in our model, attributed solely to the rise in non-tariff trade barriers. Keywords: Brexit, business investment, non-tariff barriers, productivity JEL Codes: C50, C68, E37, F41 * Corresponding author, National Institute of Economic and Social Research, a.kaya@niesr.ac.uk 1 The authors would like to thank Jagjit Chadha, Paul Gretton, Huw Edwards, Mary O'Mahony, Bart van Ark, seminar participants at The Productivity Institute and the National Institute of Economic