In the run-up to the UK’s referendum on EU membership in June 2016, extravagant claims were made by both the Remain and Leave campaigns. Leaving the EU, the so-called Remainers warned, would propel the UK into recession and mass unemployment. Brexiteers, as they were dubbed, countered with promises of enhanced sovereignty, tighter borders, and liberation from Brussels’s stifling bureaucracy. The latter won the Brexit vote (as it came to be known) by 52% to 48%. But just over a decade on from that historic decision—and six and a half years since the UK officially left the bloc—it’s less clear whether they also won the argument.

This is in large part because of geopolitical turmoil since the vote. Throughout the last decade, there has been a global pandemic, Russia has launched a full-scale invasion of Ukraine (which, in turn, caused an energy crisis across Europe), and Donald Trump has waged a series of tariff wars across the world. The difficulty of disentangling the effects of these events on the UK economy from those caused by Brexit is formidable. One analyst has even said that “we will never know precisely what the impacts of Brexit were.”

Overall, however, the sweeping transformations predicted by both Brexiteers and Remainers—positive in the former case, negative in the latter—have not occurred. The actual changes have been less dramatic, more gradual, and more mixed than either side forecast. One also has to factor in the UK’s lack of a stable leadership since the vote: when Labor’s Andy Burnham took over from Keir Starmer on July 20, he became the UK’s 7th prime minister in 10 years. This, perhaps, has so far prevented the theoretical autonomy now possessed by the UK from being fully realized. According to a poll conducted in June, 57% of Britons now believe that it was a mistake to leave the EU—meaning there are a lot of dissatisfied Brexiteers out there.

Remainers forecast economic ruin for the UK if it chose to leave the EU. According to the then-Chancellor of the Exchequer George Osborne, “A vote to leave would represent an immediate and profound shock to our economy [and] that shock would push our economy into a recession.” A recession failed to materialize, although the pound suffered its biggest-ever one-day drop on June 24, 2016, the day after the vote, falling 10% against the dollar and 7% against the euro (it still hasn’t returned to its pre-Brexit values against either currency, although Trump’s tariff wars and the pandemic are also factors here). That said, researchers broadly agree that Britain’s economy has contracted due to Brexit. According to a 2025 paper for the US National Bureau of Economic Research, UK GDP per capita is 6–8% lower than it would have been had the UK remained in the EU. Investment is down by 12–13%, employment by 3–4%, and productivity has been reduced by about 4%, according to its authors.

Immigration was a major theme of the Leave campaign. The UK Independence Party’s widely criticized poster showed a large group of Syrian refugees at the Croatia–Slovenia border in 2015, next to a massive slogan reading “Breaking Point”—and, underneath it, in smaller letters, “The EU has failed us all.” The center-right party was playing to concerns about a surge in migration over the decade and a half preceding the referendum, triggered by EU enlargements in 2004,when ten new countries joined, and in 2007. In 2000, migration to the UK from other EU countries stood at 6,000, but by 2015 it had risen to 330,000. In 2015 and 2016 alone, more than a million migrants arrived in Britain. According to a poll conducted on the day of the referendum, 33% of Leave voters said the main reason for their decision was a belief that leaving the EU “offered the best chance for the UK to regain control over immigration and its own borders.” It seems the poster had done its job.

The composition of Britain’s migrant population has changed radically since Brexit, with an increase in non-EU migration more than compensating for the reduction in arrivals from the EU. But immigration has not decreased. In fact, the UK has witnessed record levels of immigration over the last decade. In the year ending March 2023, just over three years after Britain’s withdrawal from the bloc, net migration peaked at 944,000.

Here, though, the effects of Brexit are hard to separate from those of the pandemic, after which the UK government liberalized immigration rules to boost a stricken labor market. Humanitarian routes for Syrians and Hongkongers were introduced, the skilled worker visa was extended to include medium-skilled jobs, hospitals were incentivized to hire migrant over British nurses, and an attractive new Graduate Visa came into existence. One recent study estimates that Brexit reduced the number of EU-born employees in the UK by approximately 800,000 and increased the number of non-EU-born employees by almost a million.

Irregular migration—the focal point of many Brexiteers’ concerns ahead of the vote—has also increased. In 2018, just 299 people were found crossing the English Channel in small boats, a figure that peaked at over 45,000 in 2022. Russia’s invasion of Ukraine, which began in February of that year, undoubtedly contributed to that spike; but whatever the causes of illegal migration, the UK now has less control over undocumented arrivals than it did before leaving the EU—mainly the result of losing access to the Dublin Convention on returns. Nor can British authorities use the SIS II database anymore, making it more difficult for them to detect criminality among illegal arrivals (UK law enforcement consulted SIS II 600 million times in 2019).

Also contrary to the promises of Brexiteers, bureaucracy has increased. David Cameron, the Conservative prime minister who authorized the referendum (a Remainer who resigned after the vote), aggressively downsized the UK’s civil service until 2016, with one minister saying it was at its smallest since World War II. But it has since expanded again to cope with the regulatory challenges of leaving the EU. (Ironically, throughout the 1970s and 1980s, Conservative heavyweights such as Margaret Thatcher and Arthur Cockfield advocated joining the EU’s Common Market to reduce regulatory burdens on the UK economy.)

British companies now face complex customs procedures and rules-of-origin requirements when dealing with their European counterparts, despite not having to pay any tariffs. Trade has slowed as a result. According to the UK’s Office for National Statistics, UK exports to and imports from the EU in 2025 were down 14% and 10%, respectively, compared to 2019 (although services exports from Britain to Europe have boomed over the last decade). Nor has there been a clean divergence from the EU’s legal systems, with one expert saying that “large swathes of EU law are still on the [UK] statute book”—again, despite the assurance of Brexiteers that Brussels would no longer dictate law to London.

Burnham, the UK’s new leftist prime minister, believes that Brexit was “damaging.” Although he’s said that he would like to see the UK rejoin the EU within his lifetime, he has also stressed that he has no intention of trying to make that happen himself. Remainers who forecast an economic disaster that never came might not be too bothered about that, but one wonders if the most disillusioned Brexiteers are quietly disappointed.