The Double Taxation Relief and International Tax Enforcement (Portuguese Republic) Order 2025

1 Solely for the purposes of the application of the provisions of this Protocol and of the provisions of the Convention and of the domestic laws of the Contracting States related to the exchange of information, confidentiality, and administrative assistance, members of the arbitration panel and a maximum of three staff per member (and prospective arbitrators solely to the extent necessary to verify their ability to fulfil the requirements of arbitrators) shall be considered to be persons or authorities to whom information may be disclosed. Information received by the arbitration panel or prospective arbitrators and information that the competent authorities receive from the arbitration panel shall be considered information that is exchanged under the provisions of the Convention related to the exchange of information and administrative assistance.

2 The competent authorities of the Contracting States shall ensure that members of the arbitration panel and their staff agree in writing, prior to their acting in an arbitration proceeding, to treat any information relating to the arbitration proceeding consistently with the confidentiality and nondisclosure obligations described in the provisions of the Convention related to the exchange of information and administrative assistance and under the applicable laws of the Contracting States. Part IV – Resolution of a case prior to the conclusion of the arbitration For the purposes of this Protocol and the provisions of the Convention that provide for resolution of cases through mutual agreement, the mutual agreement procedure, as well as the arbitration proceeding, with respect to a case shall terminate if, at any time after a request for arbitration has been made and before the arbitration panel has delivered its decision to the competent authorities of the Contracting States: a the competent authorities of the Contracting States reach a mutual agreement to resolve the case; or b the person who presented the case withdraws the request for arbitration or the request for a mutual agreement procedure. Part V – Type of arbitration process

1 Except to the extent that the competent authorities of the Contracting States mutually agree on different rules, the following rules shall apply with respect to an arbitration proceeding: a after a case is submitted to arbitration, the competent authority of each Contracting State shall provide any information that may be necessary for the arbitration decision to all panel members without undue delay. Unless the competent authorities of the Contracting States agree otherwise, any information that was not available to both competent authorities before the request for arbitration was received by both of them shall not be taken into account for purposes of the decision; b the arbitration panel shall decide the issues submitted to arbitration in accordance with the applicable provisions of the Convention and, subject to these provisions, of those of the domestic laws of the Contracting States. The panel members shall also consider any other sources which the competent authorities of the Contracting States may by mutual agreement expressly identify; c the arbitration decision shall be delivered to the competent authorities of the Contracting States in writing and shall indicate the sources of law relied upon and the reasoning which led to its result. The arbitration decision shall be adopted by a simple majority of the panel members. The arbitration decision shall have no precedential value.

2 Prior to the beginning of arbitration proceedings, the competent authorities of the Contracting States shall ensure that each person that presented the case and their advisors agree in writing not to disclose to any other person any information received during the course of the arbitration proceedings from either competent authority or the arbitration panel. The mutual agreement procedure under Article 23 (Mutual agreement procedure) of the Convention, as well as the arbitration proceeding under this Protocol, with respect to the case shall terminate if, at any time after a request for arbitration has been made and before the arbitration panel has delivered its decision to the competent authorities of the Contracting States, a person that presented the case or one of that person’s advisors materially breaches that agreement. Part VI – Agreement on a different resolution Notwithstanding paragraph 4 of Part I (Mandatory binding arbitration) of this Protocol, an arbitration decision pursuant to this Protocol shall not be binding on the Contracting States and shall not be implemented if the competent authorities of the Contracting States agree on a different resolution of all unresolved issues within three calendar months after the arbitration decision has been delivered to them. Part VII – Costs of arbitration proceedings In an arbitration proceeding under this Protocol, the fees and expenses of the members of the arbitration panel, as well as any costs incurred in connection with the arbitration proceedings by the Contracting States, shall be borne by the Contracting States in a manner to be settled by mutual agreement between the competent authorities of the Contracting States. In the absence of such agreement, each Contracting State shall bear its own expenses and those of its appointed panel member. The cost of the chair of the arbitration panel and other expenses associated with the conduct of the arbitration proceedings shall be borne by the Contracting States in equal shares. Part VIII – Compatibility

1 Any unresolved issue arising from a mutual agreement procedure case otherwise within the scope of the arbitration process provided for in this Protocol shall not be submitted to arbitration if the issue falls within the scope of a case with respect to which an arbitration panel or similar body has previously been set up in accordance with a bilateral or multilateral convention that provides for mandatory binding arbitration of unresolved issues arising from a mutual agreement procedure case.

2 Nothing in this Protocol shall affect the fulfilment of wider obligations with respect to the arbitration of unresolved issues arising in the context of a mutual agreement procedure resulting from other conventions to which the Contracting States are or will become parties. Part IX – Cases eligible for arbitration The provisions of this Protocol shall apply only to issues arising under the provisions of Articles 5 (Permanent establishment), 7 (Business profits) and 9 (Associated enterprises) of the Convention, excluding: a cases concerning items of income or capital gains that are not taxed by a Contracting State either because they are not included in the taxable base in that Contracting State or because they are subject to an exemption or zero tax rate provided only under the domestic tax law of that Contracting State; b cases involving the conduct of a person directly affected by the case that, by final ruling resulting from legal or administrative proceedings, has been subject to a penalty for tax fraud, wilful default or gross negligence; for this purpose, penalties for tax fraud, wilful default or gross negligence shall include the penalties for tax crimes as well as for other serious tax infringements as defined by Article 23(3) of RGIT (Regime Geral das Infrações Tributárias), enacted by the Law 15/2001, of 5 June 2001. Any subsequent provisions replacing, amending or updating these provisions would also be comprehended; c cases involving the application of domestic general anti-avoidance rules or anti-abuse rules contained in the Convention. For this purpose, the Portuguese Republic´s domestic general anti-avoidance rules shall include Articles 38 and 39 of LGT (Lei Geral Tributária) enacted by the Decree Law 398/98, of 17 December 1998. Any subsequent rules replacing, amending or updating these anti-avoidance rules would also be comprehended; d cases eligible for arbitration under the Convention on the Elimination of Double Taxation in Connection with the Adjustment of Profits of Associated Enterprises (90/436/EEC), as amended, or under any other instrument of the European Union. Part X – Entry into effect Notwithstanding the provisions of paragraph 3 of Article 28 (Entry into force) of the Convention, the provisions of this Protocol shall have effect only with respect to cases presented to the competent authority of a Contracting State on or after the date of entry into force of the Convention.

3 With reference to Articles 24 (Exchange of information) and 25 (Assistance in the collection of taxes) The terms “VAT”, “customs duties” and “excise duties” are as defined by Article PVAT.3 of the Protocol on administrative cooperation and combating fraud in the field of value added tax and on mutual assistance for the recovery of claims relating to taxes and duties and the exchange of information for customs duties is covered by the Protocol on mutual administrative assistance in customs matters, attached to the Trade and Cooperation Agreement between the European Union and the European Atomic Energy Community, of the one part, and the United Kingdom of Great Britain and Northern Ireland, of the other part. IN WITNESS WHEREOF the undersigned, duly authorised thereto, have signed this Protocol. DONE at London on this 15th day of September 2025, in two originals, in the English and Portuguese languages, both texts being equally authoritative. For the United Kingdom of Great Britain and Northern Ireland: For the Portuguese Republic: Yvette Cooper Paulo Artur dos Santos de Castro de Campos Rangel

Signed

Richard Tilbrook — Clerk of the Privy Council

Explanatory note

(This note is not part of the Order)

EXPLANATORY NOTE

The Schedule to this Order contains a Convention and Protocol (“the Arrangements”) between the United Kingdom of Great Britain and Northern Ireland and the Portuguese Republic for the elimination of double taxation with respect to taxes on income and on capital gains, the prevention of tax evasion and avoidance, and assisting international tax enforcement. This Order brings the Arrangements into effect.

Article 1 provides for citation and article 2 makes a declaration as to the effect and contents of the Arrangements.

The Arrangements aim to eliminate the double taxation of income and gains arising in one state and paid to residents of the other state. This is done by allocating the taxing rights that each state has under its domestic law over the same income and gains, and by providing relief from double taxation. There are also specific measures which combat discriminatory tax treatment and provide for assistance in international tax enforcement.

The Arrangements will enter into force on the date of the later of the notifications by each state of the completion of its domestic procedures and will take effect in each state in accordance with Article 28 of the Convention.

In accordance with paragraph 4 of Article 28, the Arrangements replace a previous Convention between the United Kingdom and the Government of Portugal set out in the Schedule to the Double Taxation Relief (Taxes on Income) (Portugal) Order 1969.

The date of entry into force will, in due course, be published in the London, Edinburgh, and Belfast Gazettes.

A Tax Information and Impact Note has not been produced for the Order as it gives effect to a double taxation agreement. Double taxation agreements impose no obligations on taxpayers. They seek to eliminate double taxation and fiscal evasion.

Footnotes