How much has leaving the EU reduced UK output?
Core argument: Estimates combining macro simulations with Decision Maker Panel micro data suggest that by 2025 Brexit had reduced UK GDP by 6–8%, investment by 12–18%, employment by 3–4% and the level of productivity by 3–4%, accumulating gradually over time.
We combine simulations based on macro data with estimates derived from micro data collected through our Decision Maker Panel survey. These estimates suggest that by 2025, Brexit had reduced UK GDP by 6% to 8%, with the impact accumulating gradually over time. We estimate that investment was reduced by between 12% and 18%, employment by 3% to 4% and [the level] of productivity by 3% to 4%. [The survey data indicate that] these large negative impacts reflect a combination of elevated uncertainty, reduced demand, diverted management time, and increased misallocation of resources from a protracted Brexit process. Firms with a higher level of pre-referendum exposure to the EU (based on our six-measure average) experienced higher investment growth than less exposed firms in the pre-referendum period between 2011 and 2015. But after 2016, investment growth was lower for these more exposed firms. [Likewise], firms with higher pre-referendum exposure to the EU had faster TFP growth prior to the referendum, but lower TFP growth afterwards - a firm with an EU exposure index of 0.1 (~ the mean), rather than 0, experienced [total factor] productivity growth of around 0.5 percentage points a year less after 2016 than it would have otherwise done.





