Bow Group report estimates rejoining EU could cost up to £41bn

A report by the Bow Group, a Conservative think tank, estimates that rejoining the European Union could cost the UK between £28 billion and £41 billion in membership fees. The report compares that range with the £17 billion fee paid in the UK's last full year of membership. It notes that the EU has not settled its next long-term budget, so the final figure could vary.

The timing is tied to an EU summit in Brussels on 20 November. The Prime Minister has said the summit is a chance to make progress on two issues: boosting UK growth and controlling illegal immigration. Supporters of closer EU ties point to access to the Schengen Information System and Eurodac, the EU fingerprint database, as tools that could help identify migrants and criminals.

Critics argue that using those systems would mean accepting European Court of Justice oversight and paying a membership fee, which they call a surrender of sovereignty. Lord David Frost, the former chief Brexit negotiator, said access to the databases would not solve illegal migration on its own. He said knowing who someone is does not help if the UK cannot send them back. He added that in 2020 the UK was open to an arrangement, but not one involving the ECJ or EU law. He also said the EU budget could be 75 to 80 per cent bigger than when the UK was last a member, which would nearly double the cost. With around 28 million households, a £28 billion fee would amount to about £1,000 per household, he said.

Norman Baker, a former Liberal Democrat minister, said his party has been consistent in viewing the single market and customs union as good things, and that rejoining could be good too, though he said he was not speaking for the party. On migration, he said a 2014 Home Office assessment under Theresa May found significant benefits from EU information and the European Arrest Warrant. He said EU members receive two million crime alerts a year about individuals, while the UK has no access to them. Any gain from Schengen Information System or Eurodac access would depend on the deal the Prime Minister negotiates, he said, and the benefits and drawbacks would need to be weighed.

Economic claims are also in dispute. Goldman Sachs has said joining the single market could increase UK GDP by 2 to 5 per cent. Nigel Farage dismissed that as fantasy economics. The debate also heard that there is a cost to staying out as well as a cost to rejoining. The Bow Group report comes from a Conservative think tank, and the Conservative Party's position is not to reopen Brexit. The argument is likely to continue before the Brussels summit.