William J. Kambas

Partner | Greenwich, New Haven, New York

Bill is a partner in the 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 working 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

‘Family Offices: Business, Not Personal,’ Wealthmanagement.com - June 11, 2018, quoted

‘S Corporations vs. C Corporations In 2018,’ TaxConnections - May 24, 2018, quoted

Skidmore College Annual Fund, President

Saint Barbara Greek Orthodox Church Endowment Fund, Chairman

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

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

‘Family Office Operations 2018: New Ideas and the Evolving Landscape of Taxation,’ Citi Private Bank - May 3, 2018, co-presenter

‘Tax reform and the family office’, Withers New York and Greenwich event - June 2018, __ speaker



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1700 East Putnam Avenue,

Suite 400,

CT 06870-1366

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New Haven

157 Church Street,

CT 06510-2100

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New York

430 Park Avenue,

10th Floor,

NY 10022-3505

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