William F. J. Ardinger

Firm: Rath Young Pignatelli. P.C
Location: Concord - NH

  • 81 North Main Street
    Concord, NH 03301
  • Tel : 603-226-2600
  • Fax : 603-226-2700

William F. J. Ardinger is a shareholder and served for three decades as the head of the firm’s Tax Practice Group. Bill focuses his practice on federal and state tax matters, business transactions, financial and wealth planning, and public policy matters. His work includes structuring business transactions in a tax-efficient manner, planning multi-jurisdictional business structures, and managing federal and state tax controversies. Bill advises non-profit healthcare organizations on how to structure affiliations that will fortify operations against the impacts of dramatic federal and state regulatory changes. Bill has been a leader of New Hampshire’s initiative to become a modern and leading jurisdiction for laws governing trusts and regulated trust companies, including representing wealthy families seeking to charter private trust companies focused solely on family interests. With respect to public policy matters, Bill represents clients before the New Hampshire Legislature and Congress on state and federal legislative and regulatory initiatives involving tax, budget, and economic development policies.

Bill is recognized in The Best Lawyers in America for tax law, and he is recognized as one of the leading corporate/commercial/tax lawyers in New Hampshire by Chambers USA: America’s Leading Business Lawyers.

Prior to joining the Rath, Young, and Pignatelli in 1989, Bill practiced law with the Washington D.C. law firm of Patton Boggs, LLP, where he represented clients on complex business tax matters and public policy matters before the federal tax legislative process, including many aspects of the 1986 Tax Reform Act. Bill was elected to the New Hampshire House of Representatives in 1980 to represent his hometown of Cornish. While in the State Legislature, Bill served on the Ways and Means Committee.

Bill lives in Concord, New Hampshire with his wife, Kassandra Spanos Ardinger, and enjoys visiting his children and grandchildren in various places.


  • Harvard Law School, J.D., cum laude, 1985
  • University of New Hampshire, B.A., summa cum laude, Economics, 1982

Bar Admissions:

  • New Hampshire
  • District of Columbia Court of Appeals
  • U.S. Tax Court

Rath Young Pignatelli. P.C

Rath, Young and Pignatelli merges traditional legal practice areas with legislative and public policy expertise. We have earned a reputation for achieving client success through skillful and creative advocacy in private party negotiations, before courts, regulatory agencies and legislatures.

Our professionals are leaders in key sectors of our economy where business and government intersect including business and finance, energy, tax, health care, environmental and insurance.