Sónia Fernandes Martins

I specialise in tax law, advising domestic and international clients on relevant tax matters, including corporation tax, VAT, stamp duty and procedural issues.

I work with clients from various sectors such as real estate, financial services, energy and infrastructure, helping them to deal with contentious matters, regulatory challenges and complex tax frameworks, both nationally and internationally. My practice is complemented by teaching and publishing articles on current tax issues, including digital taxation and anti-abuse rules.

Experience:

• Representing companies established in the Madeira Free Trade Zone in State aid recovery matters.
• Advising collective investment vehicles on the recovery of corporate income tax arising from breaches of European Union law.
• Acting for banking institutions in claims for the recovery of the Banking Sector Solidarity Surcharge and the Extraordinary Banking Sector Contribution.
• Advising transport sector companies on the recovery of the Road Service Contribution.

I am an arbitrator at the Administrative Arbitration Centre (CAAD). My career includes leadership positions in international law firms, where I coordinated teams dedicated to resolving tax disputes and controversies. I have acted in proceedings before national courts and European institutions, including the General Court and the Court of Justice of the European Union, which has given me in-depth knowledge of cross-border tax disputes, particularly at EU level.

I have been recognised in Best Lawyers (2020–2023) for Tax Law.

Professional Associations:

• Portuguese Tax Association.
• Portuguese Bar Association.

Academic Background:

• Intensive Course Pillar 2 – The Global Minimum Tax Reform, Faculty of Law of the Portuguese Catholic University – Lisbon School (2025)
• Intensive Course on Cryptoassets, Faculty of Law of the University of Lisbon (2022)
• Short Course in Digital Taxation, Faculty of Law of the Portuguese Catholic University – Lisbon School (2018)
• Accounting and Finance Programme for Lawyers, Católica Lisbon School of Business & Economics (2017)
• Short Course in Tax Law Practice, Faculty of Law of the University of Lisbon (2016)
• Postgraduate Degree in Administrative Litigation and Tax Law and Litigation (Preparation for admission to the Centre for Judicial Studies) – Faculty of Law of the University of Lisbon (2016)
• Advanced Postgraduate Course in Tax Law: Application of Anti-Abuse Rules - Faculty of Law of the University of Lisbon (2016)
• Short Course on Tax Procedure and Process, Faculty of Law of the University of Lisbon (2013)
• Postgraduate Degree in Tax Procedure and Process – University of Coimbra (2013)
• Postgraduate Degree in Non-Contractual Civil Liability of the State – Faculty of Law of the University of Lisbon (2008)
• Postgraduate Degree in Taxation – ISG Business & Economics School (2007)
• Postgraduate Degree in Legal and Administrative Sciences – Faculty of Law of the University of Lisbon (2006)
• Postgraduate Degree in Legal Practice and Business Management – Portuguese Catholic University (2004)
• Bachelor's Degree in Law – Faculty of Law of the University of Lisbon (2003)

Languages:

English and French.