British voters have “limited enthusiasm” for the post-Brexit agreement Boris Johnson’s government negotiated with the EU last year, with only one in five describing it as a “good” deal, a survey has found.

However, ahead of the fifth anniversary of the 2016 EU referendum on Wednesday, the poll also found that years of divisive political debate had changed few minds — with four out five people who voted saying they would still vote the same way.

Sir John Curtice, politics professor at Strathclyde university, who led the research for the polling group What UK Thinks and the National Centre for Social Research (NatCen), said the findings were “far from a ringing endorsement” of the Brexit trade deal.

“Five years on, it is difficult to argue that the Brexit referendum has been an unalloyed success,” Curtice wrote, noting Leavers’ limited enthusiasm for the Brexit deal. At the same time, he added, the outcome had reconciled few Remain voters to the Brexit project.

The overall tepid response to the trade deal negotiated by Lord David Frost last year found that even among Leave voters, only one in three felt it was a “good” deal, although that figure reflected the fact that some Leave voters would have preferred to have left the EU on even harder terms, with no deal at all.

Column chart of Per cent showing Enthusiasm is limited for the UK

The survey was conducted just weeks after the UK left the EU single market on January 1 and is the latest in a rolling series of polls that have been conducted by What UK Think and NatCen since 2016.

The UK-EU Trade and Co-operation Agreement (TCA) did not trigger the significant disruption predicted for UK ports this January, but did cause UK exports to the EU to fall sharply in some sectors such as agrifood, where exports fell by nearly 50 per cent in the first quarter of this year compared to 2019 and 2020.

Other broader impacts, particularly on professional services and travel, have to some extent been masked by Covid-19, which has sharply reduced leisure and business travel to Europe this year.

Despite misgivings about the post-Brexit deal, the poll continued to vindicate Johnson’s decision to make good on his 2019 election promise to “get Brexit done”, with dissatisfaction with the UK government’s handling of Brexit falling from a peak of 88 per cent in autumn 2019 during the period of prolonged parliamentary stalemate, to about 50 per cent today.

“The confidence that Leave voters had in the UK government was badly shaken when it appeared that Brexit might not happen, but it has now largely been restored,” Curtice wrote.

At the same time, the survey found that three out of four Leave voters now expect either immigration to fall or that the economy will be better off — two key metrics of Brexit — indicating that for many voters, “the detail of Brexit matters less than the principle”.

As for whether a rerun of the 2016 Referendum today would see a different result, the poll found it probably would not.

While a clear majority of those who did not vote in 2016 say they would now vote to rejoin the EU, they are likely to be cancelled out by the number of Remain voters who — even though they still wished the UK had remained a member of the EU — would not now vote because of the further upheaval of rejoining.

“We estimate that a referendum held now on ‘rejoin’ versus ‘stay out’ could well produce a narrow majority (52%) in favour of staying out,” Curtice said.

Looking to the future, Curtice said it was not clear whether public opinion would swing if future difficulties with the UK-EU TCA emerged once Covid-19 restrictions were lifted in the coming months.

Much would depend on whether the opposition Labour party, which has so far been reluctant to campaign on Brexit issues for fear of alienating Leave voters in target constituencies, was prepared to make an issue of Brexit in the future.

“Proof of the Brexit pudding will be in the eating, and the main course has been delayed by the pandemic,” Curtice told the FT.

“To make a difference, the government’s record will have to be criticised and that will depend on the extent to which the opposition is willing to tackle what they regard as the operational failures of Brexit.”