FAQ: How and when could the UK rejoin the EU?

How long could it take the UK to rejoin the EU? How would that happen? What would it look like? Well, you’ve come to the right place. 

New research from Best for Britain has established that the UK could rejoin the European Union (EU) within a single parliament, and complete negotiations in less time than it took for the UK to agree its trade deal with India.

Here’s everything you need to know about the process, the timeline and the step-by-step nature of negotiations to restore our place at the heart of Europe.

How can the UK rejoin the EU?

To rejoin the EU, the UK would need to: apply for membership; acquire candidate status; open and close accession negotiations; and finally, agree and sign an Accession Treaty. 

First, the UK would need to submit a membership application under Article 49 of the Treaty on European Union. The European Council (heads of state or government from all EU member states) would take a final decision on whether to grant candidate status. 

Next, negotiations would begin at an Intergovernmental Conference (a meeting between the EU and the candidate country). Negotiations are organised into 35 chapters, covering the full body of EU law. For each chapter, the UK would need to show how it would adopt and implement EU law and standards. 

Finally, once negotiations have been completed, the EU would draft an Accession Treaty. At this stage the European Parliament would also vote to give consent to UK membership by majority, and the Council of Ministers (made up of ministers from all member states) would need to decide unanimously to admit the UK.

The UK’s Prime Minister and the leaders of the 27 member states would then sign the Accession Treaty. The Treaty would require ratification by the UK Parliament and every member state, in line with their respective constitutional procedures. 

Would the UK be eligible to rejoin the EU?

Yes. 

To be eligible to join the EU a country must:

• Be European,
• Have stable institutions that guarantee democracy, the rule of law, human rights, and the protection of minorities,
• Have a functioning market economy,
• And have the administrative capacity to adopt EU legislation.

As a former member state, the UK would be well-placed to meet EU membership criteria. 

How long would it take for the UK to rejoin the EU?

Less than five years. 

Countries that have joined the EU have taken an average of around five years to do so  (from the opening of accession negotiations to the ratification of the accession treaty). 

However, this can be a much quicker process. For example, Finland completed the entire process – from application to accession – in just under three years. 

As a former member of the EU, and with much of our former EU legislation carried over following Brexit, it seems likely that Britain’s progress would be on the quicker side of the equation once its application has been made. 

Would the EU require the UK to hold a referendum as a condition of rejoining the EU?

No. 

EU law does not require a referendum before entering the EU.

However, having left the EU based on a referendum, it might be politically challenging to re-enter the EU without one. And, of the 13 countries who have joined the EU since 2004, 11 held referendums. This has either been a constitutional requirement, or to give the decision democratic legitimacy. The majority of these referendums were held at the conclusion of negotiations, rather than a broader ‘in/out’ question at the beginning. 

Could the UK be forced to adopt the euro?

No. 

While all new member states are formally committed to adopting the euro eventually, a country only starts the process of joining the euro after formally joining the EU. There is no deadline to join.

Crucially, eurozone membership depends on a country first joining the Exchange Rate Mechanism II (ERM II). Because joining ERM II is voluntary, countries can remain outside of the euro indefinitely by declining to join ERM II. Sweden, Romania, Poland, Hungary, and Czechia have all avoided adopting the euro in this way.

When the UK was a member of the EU, it had a formal opt-out from the eurozone which would not be restored automatically.

Would the UK be forced to join the Schengen Area?

No. 

Countries joining the EU are formally required to accept Schengen rules, however they do not join the Schengen area automatically upon entry.

Furthermore, Ireland has a formal opt-out from the Schengen area. Due to the Common Travel Area between Ireland and the UK, both parties are committed thanks to the Good Friday Agreement to not have a hard land border between Northern Ireland and the Republic of Ireland. Therefore, for the UK to join the Schengen Area, Ireland would have to join at the same time. It is hard to envision that the EU would pressure Ireland to join Schengen during any UK-EU negotiations. 

When the UK was a member of the EU, it had a formal opt-out from the Schengen area that would not be restored automatically. 

This example, and Britain’s before, also illustrate that it is possible to accept the principle of freedom of movement without being a part of the Schengen Area (which would remove passport checks). 

Why is the UK different to other candidate countries?

No candidate country has faced the accession process as a former member state. Compared to other candidate countries, several factors should ease the UK’s path to membership. Much of the UK’s current legislation remains EU legislation that has been carried over following Brexit. The UK is already pursuing market integration in some sectors (for example, in agrifood and electricity). And the UK and the EU have many shared values and norms. 

In addition, Best for Britain’s polling – carried out by YouGov – suggests that a majority of Brits (53%) want to rejoin the EU, with just a third (32%) opposed. 

Why would the EU want the UK to rejoin?

The UK is the fifth largest economy in the world; behind only the US, China, Germany, and Japan. By joining the EU, the UK would provide a great deal more power to the bloc. 

Research by Frontier Economics, commissioned by Best for Britain, suggests that if the UK were to join the EU then the current bloc could experience an increase in GDP of around $90bn in the long run and see its exports rise by almost $50bn in one year.