Brexit at 10: a smaller economy, seven PMs, and no end to the debate

Ten years after British voters chose to leave the European Union, the United Kingdom is grappling with an economy that independent analysts estimate is somewhere between 6% and 8% smaller than it would have been had the country stayed. That’s not a rounding error. For a G7 nation, it’s a generational wound.

The June 23, 2016 referendum set off a chain of political chaos that nobody fully predicted. Seven prime ministers have held office since the vote — David Cameron, Theresa May, Boris Johnson, Liz Truss, Rishi Sunak, and now two successors navigating what one Treasury official described as “a permanent state of economic catch-up.” Truss lasted 45 days. The instability alone rattled investor confidence for years.

The economic toll is hard to ignore

The Centre for European Reform, among others, has consistently tracked what economists call the “Brexit gap” — the difference between where UK GDP actually landed and where modelling suggests it would have gone inside the single market. By most credible estimates, that gap sits at £140 billion annually. Trade in goods with the EU dropped sharply after new customs rules kicked in during early 2021. Small businesses bore the brunt. Many simply stopped exporting to Europe altogether because the paperwork wasn’t worth it.

Inflation hit harder in Britain than in comparable European economies between 2022 and 2024, partly due to supply chain friction that analysts tied directly to post-Brexit border arrangements. Food prices were a particular flashpoint.

Demographics shifted in ways few anticipated

Free movement ended. But the UK didn’t get less immigration — it got different immigration. Net migration actually hit record highs in the years following Brexit, driven by arrivals from India, Nigeria, and other Commonwealth nations rather than from Eastern Europe. The Polish plumbers and Romanian nurses who’d filled critical gaps in construction and healthcare largely left or stopped coming. The NHS still hasn’t fully recovered its staffing baseline from 2016.

A senior policy adviser at a London think tank put it plainly: “We didn’t reduce immigration. We just made it harder for the people we actually needed.”

So where does Britain stand now?

There’s been a quiet reset in tone if not in policy. The current government has negotiated a closer relationship with Brussels on defence and some regulatory alignment, stopping well short of rejoining the single market or the customs union. “Re-entry” remains politically toxic in Westminster even as polls consistently show a majority of British adults now believe Brexit was a mistake — a figure that’s held steady since around 2022.

Young voters, who opposed Brexit in 2016 at roughly 75%, are now in their thirties and forties. Their political weight is growing.

Still, a formal reversal isn’t coming anytime soon. The political cost is too high, the legal complexity too daunting, and the national exhaustion too real. Britain will keep negotiating at the margins, chipping away at trade friction, trying to attract the workers it needs.

The question isn’t whether Brexit hurt. Most economists settled that argument years ago. The question now is how much of the damage can actually be undone.