Ask Full Fact: How long would leaving the EU take?
How long will it take to leave the EU and how many new treaties is it likely to take?
We asked an expert about the process of leaving the EU earlier this year.
Under Article 50 of the Lisbon Treaty, the UK would have a maximum of two years to negotiate its withdrawal after announcing its intention to leave the EU. This negotiation period can be extended, but such an extension would have to be agreed by all other member countries.
A quicker option would be to simply repeal the European Communities Act 1972, and immediately leave the EU. But this would be in breach of international law and probably make it more difficult to strike a favourable trade agreement afterwards.
There are several alternatives to EU membership so it’s not possible to say how many new treaties the UK would choose to strike or how long this process would take. However, it is reasonable to expect that it would take several years.
The House of Commons library has also produced a report outlining the exit process and possible future treaty arrangements. The report is downloadable from this page.