William L. Inchoco

Bio headshot of William L. Inchoco.

Of Counsel

Location: Annapolis Office
Phone: 202-381-1261
Fax: 888-235-8405
Email: Contact Us

With more than 15 years of experience, William is an accomplished international tax professional with a proven track record of results blending business, legal, public policy, and taxation expertise in advising multi-national business organizations.

William provides invaluable counsel for clients operating in an environment of intense scrutiny and challenges brought about by the changing tax laws and ever-increasing regulatory environment. He has extensive expertise in the area of international taxation with specific expertise in corporate reorganizations, global restructuring, as well as U.S. inbound/outbound tax issues. He advises companies on emerging issues regarding 2017 Tax Reform legislation (i.e., Sec. 965, GILTI, FDII, and BEAT) and provide insights on its impact on existing business models. He also advises companies on tax legislation and developments around the world including the impact of EU Directives, OECD guidelines, MLI, and unilateral actions (i.e., DST).

William joined Frost Law in 2021 as Of Counsel with combined Big Four and corporate experience. Previously, he served as the International Tax Senior Advisor with the Global Tax Operations group at IBM Corporation in New York. His previous experience also included positions at Deloitte Tax LLP, Ernst & Young LLP.

Areas of Practice

  • International Taxation
  • Transfer Pricing
  • Customs and Trade
  • Corporate reorganizations and Global Restructuring

Bar Admissions

  • Foreign Jurisdiction


  • Harvard Law School, International Tax Program Fellow
  • Harvard Kennedy School, Master’s in Public Administration
  • Ateneo de Manila University, A.B. Political Science

Professional Organizations and Memberships

  • International Fiscal Association Westchester, NY/CT Region, Executive Vice-President


  • Lecturer in international tax at Fairfield University, Dolan School of Business

Published Works