This report provides new, robust estimates of the economic cost to the EU of additional restrictions, and the potential economic gain that could result from liberalisation. Concludes1) Cross-border data flows are central to the EU economy, and especially its trade and investment. Many sectors, including high-value manufacturing, IT and information services, media, and cultural sectors, are highly reliant on data 2) The difference between a path that is moderately liberalising and one that is moderately restrictive is economically significant: worth a little over 1.5% in EU GDP per year 3) A moderately restrictive scenario is one in which the EU is unable to rely on GDPR transfer mechanisms, and in which trade partners increase their overall levels of restrictions on cross-border data flows. Our modelling suggests that such a scenario leads to a reduction in EU exports of around 4%, and in 1% of GDP per year 4)The majority of the pain is self-inflicted: a majority of the EU’s export losses in restrictive scenarios (around 58%) come from an increase in its own restrictions than from partner actions 5)By contrast, if the EU and major trade partners adopted measures to facilitate cross-border data transfers, EU exports as a whole would grow by a little over 2% per year, adding 0.6% to GDP per year 6) The impacts are likely to affect both large and small businesses. In EU manufacturing, small and medium enterprises account for 23% of exports 7)Assessing the impact of data flows on SMEs in service sectors is challenging due to data limitations. However, we know that SMEs account for 61% of the turnover of EU data-reliant services sectors