William Thomas KC

Ranked in 2 Practice Areas

Band 1

Public International Law

UK-wide

3 Years Ranked

Band 3

International Arbitration

UK-wide

6 Years Ranked

Ranked in Guides

Global 2025

About

Provided by William Thomas KC

Practice Areas

Will specialises in international commercial arbitration, investment arbitration and public international law, and has particular expertise in the extractives, TMT and projects sectors. He has represented parties, as counsel and advocate, in numerous institutional and ad hoc arbitral proceedings, including before ICC, LCIA, CAS, ICSID and UNCITRAL tribunals. Will has also acted for parties in proceedings before the International Court of Justice, the Iran-US Claims Tribunal and the European Court of Human Rights.

Career

Will holds a degree from the University of Cambridge, and is an English solicitor-advocate and King’s Counsel (KC). He has lectured regularly on international law at King’s College, London and Sciences Po, Paris. Will is also a CEDR-accredited mediator.

Chambers Review

Provided by Chambers

UK

Public International Law - UK-wide

Band 1

Individual Editorial

William Thomas KC is head of the firm's PIL disputes, litigation and arbitration group. He has a broad PIL practice with a strong focus on Middle Eastern jurisdictions. He exhibits considerable strength in matters concerning the Law of the Sea and boundary disputes, and also has significant experience appearing before the ICJ.

Learn more about this team❖View ranking table

International Arbitration - UK-wide

Band 3

Individual Editorial

William Thomas KC's arbitration practice includes complex disputes arising from the telecoms industry. He expertly acts for both claimants and sovereign states in big-ticket BIT disputes.

View ranking table

Strengths

Provided by Chambers

Will is devastating as a cross-examiner. He is extremely forensic; he manages the detailed evidence and the big picture. He did a great job keeping everything accessible for the client.

Public International Law respondent
UK

Will is an experienced and astute PIL practitioner. Clients love working with him. He is very focused and an excellent advocate.

Public International Law respondent
UK

Will is very collaborative as well as being analytically sharp.

Public International Law respondent
UK

Will has great judgment and is very clear in thinking through tasks. He is also very collaborative as well as being analytically sharp.

International Arbitration respondent
UK

Will is a thoughtful lawyer and a very persuasive advocate.

International Arbitration respondent
UK

Will has extensive knowledge. He has highly impressive skills and is a pleasure to work alongside.

International Arbitration respondent
UK

Will is devastating as a cross-examiner. He is extremely forensic; he manages the detailed evidence and the big picture. He did a great job keeping everything accessible for the client.

Public International Law respondent
UK

Will is an experienced and astute PIL practitioner. Clients love working with him. He is very focused and an excellent advocate.

Public International Law respondent
UK

Will is very collaborative as well as being analytically sharp.

Public International Law respondent
UK

Will has great judgment and is very clear in thinking through tasks. He is also very collaborative as well as being analytically sharp.

International Arbitration respondent
UK

Will is a thoughtful lawyer and a very persuasive advocate.

International Arbitration respondent
UK

Will has extensive knowledge. He has highly impressive skills and is a pleasure to work alongside.

International Arbitration respondent
UK

Filter by

London (Firms)

Banking & Finance: Big-Ticket

Alex Mitchell

Band 2

William Thomas KC

UK Guide 2025

Public International Law + 1 more ranking

About

Practice Areas

Career

Chambers Review

UK

Public International Law - UK-wide

Individual Editorial

International Arbitration - UK-wide

Individual Editorial

Strengths

Discover other Lawyers at Freshfields

London (Firms)

Discover other Lawyers at
Freshfields