Certified accountants must hold at least 51% of the share capital and respective voting rights of accounting firms. Up to 2024, non-EU nationals could only register with the Order of Certified Accountants subject to reciprocity. Since then, 
"CHAPTER II - Exercise of the profession
Article 9 - Professional title and exercise of reserved acts
1 - The attribution of the professional title of certified accountant, its use and the exercise of acts expressly reserved by law for certified accountants, in accordance with article 30 of Law no. 2/2013, of 10 January, depend on registration in the Order.
2 - The following are also certified accountants, after registration with the Order and for the purposes set out in the previous paragraph:
a) Professionals who are nationals of Member States of the European Union and the European Economic Area, who obtain recognition of their respective professional qualifications, under the terms set out in Law No. 9/2009, of March 4;
b) Professionals who have obtained qualifications outside Portugal, as long as they obtain the necessary qualifications and meet the other requirements for registration, under the terms set out in this Statute and other legislation in force.
3 - The professionals referred to in article 123 may also carry out the activity.
4 - The professionals mentioned in paragraphs 2 and 3 who practice the profession of certified accountant in Portugal are subject to the professional and ethical rules applicable to Portuguese certified accountants, without prejudice to the rules of the State of origin to which they must continue to be subject. .
[...]
CHAPTER IV - Obtaining, suspending and losing the status of certified accountant
 Article 16 - Registration conditions
1 - The general conditions for registration as a certified accountant are:
a) Have suitability to exercise the profession;
b) Not be inhibited from exercising the profession or be in a situation of incompatibility, as defined in this Statute and other applicable regulations;
c) Have not been declared incapable of managing their persons and assets by a final and unappealable sentence;
d) Possess the academic qualifications required in the following article;
e) Attend professional or curricular internship or training, depending on the case, and obtain approval in the final internship or training exam, to be organized and carried out by the Order, under the terms defined in this Statute and in the internship regulations.
2 - For the purposes of paragraph a) of the previous paragraph, the following are presumed to be unsuitable for exercising the profession:
a) Those convicted of committing an intentional crime, with a final and unappealable sentence of a fiscal, economic or financial nature, unless rehabilitation is granted;
b) Those who make false statements at the time of registration;
c) Those declared habitual.
3 - Verification of lack of suitability is the responsibility of the jurisdictional council and is always the subject of disciplinary proceedings.
4 - (Revoked.)
5 - (Revoked.)
6 - In exceptional cases, and by order of the member of the Government responsible for the area of finance, the professional title of certified accountant may be granted on a transitional basis to certified accountants whose training was obtained in a third State, provided that it is recognized by a State Member of the European Union.
7 - Members who have voluntarily canceled their registration may re-register as long as they respect the conditions listed in this article.
[...]
Article 116 - Legal nature and types
1 - Professional companies of certified accountants are civil companies, endowed with legal personality, and may adopt the legal types provided for in the Commercial Companies Code or others legally provided for.
2 - The share capital and respective voting rights of professional companies of certified accountants are held in at least 51% by certified accountants, and the management or administrative bodies of said companies must be integrated in at least 51% of certified accountants.
[...]
CHAPTER XII - Internal market standards
Article 123 - Right of establishment
1 - The recognition of professional qualifications of nationals of a Member State of the European Union or the European Economic Area obtained outside Portugal, for registration as a member of the Order, is regulated by Law no. 9/2009, of 4 March.
2 - The professional who wishes to register with the Order under the terms of the previous number and who provides services, in a subordinate or autonomous manner or as a member or who acts as an administrator or manager in the Member State of origin, within the scope of an associative organization of professionals, observing the provisions of no. 4 of article 37 of Law no. 2/2013, of January 10, must identify the organization in question in the request submitted under the terms of article 47 of Law no. 9/2009, of March 4th.
3 - Without prejudice to what is established in the previous paragraphs, the professional must also comply with the requirements established in customs tax legislation, to practice in another member state. [...]" (Decree-Law No. 452/99 of 5 November 199, "Statute of the Order of Certified Accountants, as amended by Law N.º 68/2023 of 7 December 2023 (effective on 1 March 2024))
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"Article 9 - Professional title and practice of the profession
1 - Professionals registered with the Order are designated as certified accountants, under the terms of these Statutes, being assigned, exclusively, the use of that professional title, as well as the exercise of the respective profession.
2 - They are also certified accountants, after registration with the Order and for the purposes set out in the previous number:
a) Professionals who are nationals of Member States of the European Union and the European Economic Area, who obtain recognition of their respective professional qualifications, pursuant to Law No. 9/2009, of March 4, amended by Laws no. 41/2012, of August 28, and 25/2014, of May 2, pursuant to these Bylaws;
b) Professionals who have obtained the qualifications outside Portugal, under reciprocal conditions, provided that they obtain the same qualifications as necessary and meet the other requirements for registration, under the terms provided for in this Statute and in other legislation in force.
[...]
Article 16 - registration conditions
1 - The general conditions for registration as a certified accountant are: [...]
4 - Non-European Union citizens who are domiciled in Portugal and who meet the other conditions required in paragraph 1 are allowed to register, provided that there is reciprocal treatment by their country of origin, and the requirements may be required of the next issue.
[...]
Article 116 - Legal nature and types
1 - Professional companies of certified accountants are civil companies, endowed with legal personality, and may adopt the legal types provided for in the Commercial Companies Code or others legally provided for.
2 - The share capital and respective voting rights of professional companies of certified accountants are held in at least 51% by certified accountants, and the management or administrative bodies of said companies must be integrated in at least 51% of certified accountants.
[...]
Article 123 - Right of establishment
1 - The recognition of professional qualifications of nationals of a Member State of the European Union or the European Economic Area obtained outside Portugal for registration as a member of the Order is regulated by Law no. 9/2009, of 4 March, as amended by Laws 41/2012, of 28 August, and 25/2014, of 2 May, without prejudice to special conditions of reciprocity if the qualifications in question were obtained outside the European Union or the European Economic Area.
2 - The professional who wishes to register with the Order under the terms of the previous number and who provides services, in a subordinate or autonomous manner or as a member or who acts as a manager or administrator in the Member State of origin, within the scope of an associative organization of professionals, must identify the organization in question in the request submitted pursuant to article 47 of Law no. 9/2009, of March 4, amended by Laws no. 41/2012, of August 28, and 25/ 2014, May 2nd.
3 - Without prejudice to what is established in the previous paragraphs, the professional must also comply with the requirements established in customs tax legislation, to practice in another member state.[...]" (Decree-Law No. 452/99 (1999-11-05), as amended by Law No. 139/2015 (2015-09-07), Articles 9, 16 and 116 [google translation])
Decree-Law No. 452/99 of 5 November 199, "Statute of the Order of Certified Accountants, as amended by Law N.º 68/2023 of 7 December 2023 (effective on 1 March 2024).
Decree-Law No. 452/99 of 5 November 199, "Statute of the Order of Certified Accountants, as amended by Law No. 139/2015 of 7 September 2015
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