William J. Kambas

Partner | New York, New Haven, Greenwich

Bill is a partner and the Regional Division Leader of the US private client and tax team.

He focuses on tax planning for multi-national and multi-state personal, active business, and investment activities, with a particular emphasis on tax structuring and choice of business entity for US and non-US business owners and investors.

Bill has represented a wide variety of private and public businesses, including family-owned, start-ups and multi-million dollar enterprises on purely domestic as well as inbound and outbound business transactions, cross-border investments (whether made directly or through investment funds or joint ventures), and qualification for US tax treaty benefits. In particular, he has considerable experience advising non-US persons on the US income and estate tax consequences and tax planning associated with the ownership of US real estate (whether residential or commercial, development, operational, or for personal use).

An integral part of Bill’s work involves assisting families, their family offices, and/or family enterprises with the formation, management, and/or periodic evaluation of multinational and/or multi-generational centralized control and management structures, such as family offices and private trust companies.

In addition to numerous speaking engagements, organization memberships and publications, Bill has also been featured as a guest lecturer at the Hellenic Studies Program at Yale University, the Columbia Business School at Columbia University, the University of Connecticut School of Law and the Charles F. Dolan School of Business at Fairfield University.

Secretary Mary Marshall





State of Connecticut, 2003

State of New York, 2004

United States Tax Court, 2004

‘Supreme Court finds North Carolina can’t tax trust income,’ Tax Notes - June 24, 2019, quoted

Skidmore College Annual Fund, President

Saint Barbara Greek Orthodox Church Endowment Fund, Chairman

International Fiscal Association (Westchester, NY and Connecticut Region), Executive Committee

‘Family Forum - Stories from the Front Lines: Dynamic Estates,’ New York State Bar Association, Family Governance Symposium - July 15, 2019, co-presenter

‘Essentials of Family Offices for the Estate Planner - A Primer on Functions, Structures, and Related Issues’ at the 53rd Annual Heckerling Institute on Estate Planning by the University of Miami School of Law - January 17, 2019, co-presenter

‘Planning the Estate: Multijurisdictional Estate Planning with a Family Business,’ Columbia University Business School Family Business Management - November 13, 2018, co-presenter



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New York

430 Park Avenue,

10th Floor,

NY 10022-3505

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New Haven

157 Church Street,

CT 06510-2100

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1700 East Putnam Avenue,

Suite 400,

CT 06870-1366

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