Timeline and Key Documents

 Click or tap on the links below to go to:

  • The Timeline - key events following the referendum on EU membership.
  • Future Dates - View the important upcoming dates relating to EU Exit, including the Assembly’s democratic consent vote on the Protocol on Ireland/Northern Ireland.



The Timeline

This is a timeline outlining the key events following the referendum on EU membership. It also provides links to key documents and legislation relating to the negotiations and EU Exit.


  • 23 June 2016 - Referendum

    The UK votes in a referendum to leave the EU by 52% to 48%.

  • 29 March 2017 - Article 50

    Then UK Prime Minister Theresa May triggers Article 50, the legal mechanism for a Member State to leave the EU.

  • 19 June 2017 - Negotiations begin

    Negotiations begin between the UK Government and Michel Barnier, on behalf of the EU.

  • 9 December 2017 - Joint Report

    The UK and EU release a Joint Report on their agreement in principle on citizens’ rights, the unique circumstances in Northern Ireland, and the financial settlement.

  • 26 June 2018 - EU Withdrawal Bill

    The European Union (Withdrawal) Bill 2018 receives Royal Assent.

  • 21 June 2019 - North South Cooperatation

    Publication of the mapping exercise on North – South cooperation carried out during Phase 1 of the negotiations by the UK and EU.

  • 17 October 2019 - Withdrawal Agreement and Political Declaration

    Agreement is reached between the negotiators on the Withdrawal Agreement, including the Protocol on Ireland/Northern Ireland and Political Declaration.

  • 11 January 2020 - Assembly Restored

    The Northern Ireland Assembly is restored with the ‘New Decade, New Approach’ agreement.

  • 23 January - Withdrawal Bill receives Royal Assent

    The European Union (Withdrawal Agreement) Bill 2020 receives Royal Assent.

  • 24 January 2020 - Withdrawal Agreement signed

    The Withdrawal Agreement is signed by the EU and UK.

  • 31 January 2020 - UK leaves the EU

    The United Kingdom officially leaves the European Union at 11pm.

  • 1 February 2020 - Transition period begins

    The Withdrawal Agreement enters into force and the UK enters the transition period.

  • 2 March 2020 - Negotiations on Future Relationship

    Negotiations on the Future Relationship formally begin.

  • 30 March 2020 - First meeting of Joint Committee

    The first meeting of the Withdrawal Agreement Joint Committee is held. The Committee oversees the implementation of the Withdrawal Agreement and Protocol on Ireland/Northern Ireland.

  • 1 December 2020 - Joint Committee adopts decisions on the Protocol

    The Joint Committee adopts decisions providing clarity on outstanding issues relating to the Protocol.

  • 24 December 2020 - EU and UK reach a deal

    EU and UK negotiators reach a deal on a future relationship.

  • 30 December 2020 - Future Relationship Bill receives Royal Assent

    The European Union (Future Relationship) Bill 2020 receives Royal Assent.

  • 1 January 2021 - EU-UK Trade Agreement

    The transition period ends and the EU-UK Trade and Cooperation Agreement provisionally enters into force.

  • 3 March 2021 - UK extends grace periods

    UK unilaterally takes ‘temporary technical steps’ to extend until 1 October grace periods relating to the Protocol on Ireland/Northern Ireland.

  • 15 March 2021 - EU Legal Action

    Following the UK’s unilateral move, the EU launches legal proceedings against the UK. In light of the Windsor Framework, the EU did not proceed with its legal action.

  • 27 April 2021 - European Parliament ratifies deal

    The European Parliament ratifies the EU-UK Trade and Cooperation Agreement, passing an accompanying resolution.

  • 21 July 2021 - UK Command Paper

    The UK Government publishes a Command Paper on its proposed approach to the Protocol.

  • 6 September 2021 - Grace periods extended

    The UK Government announced it will continue to operate the Protocol on the current basis, including the grace periods currently in force.

  • 13 October 2021 - Commission proposals

    The European Commission publishes proposals on engagement with Northern Ireland stakeholders and authorities,  customs, Sanitary and Phytosanitary (SPS) issues and medicines. The UK and EU then entered intense negotiations on the Protocol.

  • 17 December 2021 - Medicines supply under the Protocol

    The European Commission puts forward proposals to ensure the continued long-term supply of medicines from Great Britain to Northern Ireland.

  • April 2022 - Medicines supply under the Protocol

    The European Parliament and the EU Council approved changes to EU law which aim to guarantee the continued supply of medicines to Northern Ireland.

  • 12-13 May 2022 - EU-UK Parliamentary Partnership Assembly (PPA)

    The first meeting of the EU-UK Parliamentary Partnership Assembly (PPA) took place in Brussels.

  • 13 June 2022 - Northern Ireland Protocol Bill

    UK Government published the Northern Ireland Protocol Bill, which would disapply core parts of the Protocol relating to trade in goods, subsidy control, the role of the Court of Justice of the EU, plus allow changes to VAT. In light of the Windsor Framework, the UK did not proceed with the NI Protocol Bill, which falls at the end of the parliamentary session.

  • 15 June 2022 - EU Responds with legal action

    The EU launched infringement proceedings against the UK “for breaking international law”. It also published additional details on its solutions of October 2021 to ease movement of goods between GB and NI (EU position papers on customs and sanitary and phytosanitary issues). Following the conclusion of the Windsor Framework, the EU stated, “there will no longer be grounds for the existing Commission legal proceedings against the United Kingdom relating to the Protocol on Ireland / Northern Ireland.”

  • July 2022 - UK legislation and EU legal action

    The Northern Ireland Protocol Bill completed its stages in the House of Commons and proceeded unamended to the House of Lords. The European Commission launched four new infringement procedures against the UK for not properly implementing the Protocol. In light of the Windsor Framework, the UK and EU did not proceed with their respective legal actions.

  • 22 September 2022 - Retained EU Law Bill

    The Retained EU Law Bill was introduced to Parliament.

  • 4 October 2022 - Civil Society Forum

    The first meeting of the Civil Society Forum was held in Brussels.

  • 9 January 2023 - EU-UK data-sharing agreement

    The UK and EU reach an agreement on sharing trade data.

  • 27 February 2023 - The EU and UK agree in principle the ‘Windsor Framework’

    The UK Government and European Commission reach an agreement in principle on the Protocol on Ireland/Northern Ireland, called the Windsor Framework. This revises the Protocol in a number of areas and covers customs, agri-food, medicines, VAT and excise, plus a new mechanism for the involvement of the NI institutions.

  • 29 June 2023 - Retained EU Law Act

    The Retained EU Law (Revocation and Reform) Bill receives Royal Assent.

  • 1 October 2023 - Windsor Framework Implementation

    Elements of the new system under the Windsor Framework came into effect. The UK Internal Market Scheme expanded the range of businesses which can declare their goods ‘not at risk’ of moving into the EU single market. The NI Retail Movement Scheme established a system with reduced paperwork and simpler certification requirements for retail agri-food (supermarket foods). These products can meet UK (not EU) public health standards. Identity checks are reduced to 10% of all consignments of retail goods and some new labelling requirements entered into force.

  • 31 January 2024 - UK post-Brexit border controls

    The UK Government introduced the first phase of its post-Brexit border controls on certain goods from the EU (including Ireland).

  • 31 January 2024 - UKG Command Paper

    The UK Government published a Command Paper ‘Safeguarding the Union’, which paved the way for the return of the NI Assembly and Executive.

  • 30 April 2024 - UK post-Brexit border controls

    The UK Government introduced documentary checks and physical and identity checks for medium-risk animal products, plant and plant products imported to Great Britain from the EU. These checks will apply to imports from Ireland at a later date.



Future Dates

Important upcoming dates relating to EU Exit, including the introduction of checks and controls, and the Assembly’s democratic consent vote on the Protocol on Ireland/Northern Ireland.



By 31 July 2024


Windsor Framework: The UK should give the European Commission a progress report on the completion of SPS inspection facilities in NI (and then every three months until the requirements are met).

30 September 2024

The full UK Internal Market Scheme will take effect for the movement of goods from GB to NI: full international customs requirements for traders are removed and simplified procedures apply.

From October 2024

Windsor Framework:  Scheme for business to consumer parcels (authorisation and monitoring of carriers) should be in place.

From October 2024

Windsor Framework: labelling requirements extended to all dairy products, such as UHT milk and butter. The Government would propose the application of this across the UK from this point, in consultation with the Scottish and Welsh Governments. The frequency rate of identity checks on retail goods consignments will be further reduced to 8%.

From 31 October 2024

UK border controls: The UK Government will introduce Safety and Security declarations for EU imports. A reduced dataset for imports will be introduced.


For 'non-qualifying' goods moving from Northern Ireland or Ireland to GB, documentary and risk-based identity and physical checks on medium-risk animal products, plants, plant products and high-risk food and feed of non-animal origin will be introduced.*


*The Government will confirm the date for the commencement of physical checks, which won't be before October 2024.

31 December 2024

By this date, the first vote will take place in the Northern Ireland Assembly on the continued application of Articles 5-10 of the Protocol on Ireland/Northern Ireland, as outlined in the democratic consent mechanism. Read our explainer on the consent mechanism.

End of 2024

The UK’s Electronic Travel Authorisation Scheme applies worldwide to relevant visitors to the UK.

1 July 2025


Windsor Framework: final SPS inspection facilities should be in place in Northern Ireland.

From 1 July 2025

Windsor Framework: all retail goods (other than goods sold loose) should be individually labelled (with some exceptions for those not subjected to EU official controls (e.g. confectionery, chocolate, pasta, biscuits, coffee). The rate of identity checks on retail goods consignments will be reduced to 5%.

31 December 2025

The grace period for veterinary medicines ends. By this date, the UK must ensure that supplies of veterinary medicines to Northern Ireland conform with relevant EU law and the provisions of the Protocol.

31 December 2025

First review of the EU-UK Trade and Cooperation Agreement, to take place every five years.

30 June 2026

Adjustment period for fishing ends, annual negotiations on access to fishing waters begin.

By 1 January 2027

Windsor Framework: review of Enhanced Coordination Mechanism on Vat and Excise to take place.

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