This paper provides a timeline of the major events leading up to the EU referendum and subsequent dates of note, looking ahead to expected events as the UK and EU negotiate the UK's exit.

In a referendum held on 23 June 2016, the majority of those who voted chose to leave the European Union.

On 29 March 2017, in writing to European Council President Donald Tusk, the Prime Minister formally triggered Article 50 and began the two-year countdown to the UK formally leaving the EU (commonly known as ‘Brexit’).

The UK had long been expected to leave the European Union at 11pm on 29 March 2019.  However, following a House of Commons vote on 14 March 2019, the Government sought permission from the EU to extend Article 50 and agree a later Brexit date.

On 20 March 2019 the Prime Minister wrote to European Council President Donald Tusk, asking to extend Article 50 until 30 June 2019.

Following a European Council meeting the next day, EU27 leaders agreed to grant an extension comprising two possible dates: 22 May 2019, should the Withdrawal Agreement gain approval from MPs; or 12 April 2019, should the Withdrawal Agreement not be approved by the House of Commons.

On 2 April 2019, the Prime Minister announced she will seek a further extension to the Article 50 process and offered to meet the Leader of the Opposition to agree a deal that can win the support of MPs.

At a meeting of the European Council on 10 April 2019, the UK and EU27 agreed to extend Article 50 until 31 October 2019.

On 19 October 2019, the Prime Minister’s new Brexit deal was lost on amendment in the Commons.  In accordance with the European Union (Withdrawal) (No. 2) Act 2019 – commonly known as the ‘Benn Act’ – the Prime Minister wrote to European Council president Donald Tusk, to request an extension to the Brexit process.

On 28 October 2019, EU Ambassadors agreed a further Brexit extension to 31 January 2020. The Prime Minister confirmed the UK’s agreement to this.

On 12 December 2019, Boris Johnson won a majority in the UK General Election and reaffirmed his commitment to ‘get Brexit done‘ by 31 January 2020.

On 23 January 2020, the European Union (Withdrawal Agreement) Act received Royal Assent.  This is the legislation that will implement the withdrawal agreement negotiated by the UK and the EU.

At 11pm on 31 January 2020, the UK left the European Union and entered a transition period that is due to run until the end of the year.

This paper provides a timeline of the major events leading up to the referendum and subsequent dates of note, including Brexit Day itself. 

This paper also provides information on negotiations on the UK-EU future relationship as the implementation period continues.