Justin Mazer

Justin Mazer

US Tax Underwriting Counsel 

Justin began his tax career in 2010 with PwC’s Seattle office, specialising in international tax. In 2018, he was seconded to PwC’s London office where he spent two years advising European-based multinational companies on cross-border tax matters and M&A transactions. He then returned to PwC Seattle, continuing to advise both US and non-US clients ranging from Fortune 500 companies to start-ups.


Justin’s experience at PwC focused on international tax and M&A advisory across the deal lifecycle, including buy-side and sell-side due diligence and tax structuring from pre-acquisition through post-deal integration. He supported clients on complex cross-border transactions and restructurings, managing the design and implementation of operating models and legal entity structures aligned with clients’ commercial objectives.

In addition to his transactional work, Justin has significant experience with US GAAP tax provisions under ASC 740 and international tax reporting for US federal income tax purposes.

Justin is a US-trained lawyer and a member of the Washington State Bar and the State Bar of California. He holds a Juris Doctor from the University of San Diego School of Law and a Bachelor of Science in Computer Science from the University of Delaware.