Serving Our Community’s Legal Needs For Over 70 Years


John G. De Koster

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Practice Areas

  • Estate Planning and Probate
  • Real Estate Law
  • Taxation Law
  • Corporate Law


John has engaged in the general practice of law for over 40 years. He spends a majority of his time addressing estate planning and probate matters, real estate law, and tax planning and preparation. Before joining De Koster & De Koster, he practiced for four years in the Office of the Solicitor of the United States Department of the Interior in Washington, D.C.

John obtained his Doctor of Jurisprudence from the University of Colorado School of Law graduating in the top 10% of his class and awarded Order of the Coif. While in law school he worked in the legal aid clinic representing criminal defendants and clerked for the Denver firm of Lohf & Barnhill.

Before attending the University of Colorado School of Law, John graduated with distinction and honors from Iowa State University with a major in political science and a minor in history. While at Iowa State University he sang in the University Chorus and participated in residence hall student government.

John is an member of the American Reformed Church in Hull, Iowa, where he has served as both an elder and deacon and has taught adult Sunday school classes. He is the president of the Hull Community Foundation, a board member of the Hull Industrial Development Corporation, and serves as the Secretary/Treasurer of the Hope Cemetery Association. In his free time he golfs, follows the Cleveland Guardians and Iowa State Cyclones and travels, when time permits.


  • University of Colorado School of Law, Boulder, Colorado
    • J.D., Doctor of Jurisprudence - 00/1975
    • Honors: Order of the Coif
  • Iowa State University, Ames, Iowa
    • B.S. - 1972
    • Honors: cum laude
    • Honors: With Honors

Bar Admissions

  • Iowa, 1975
  • U.S. Supreme Court, 1978

Pro-Bono Activities

  • President of the Hull Community Foundation
  • Board Member of the Hull Industrial Development Corporation
  • Secretary/Treasurer of the Hope Cemetery Association

Representative Clients


Past Positions

  • United State Department of the Interior, Attorney
  • Lohf & Barnhill, Clerk, 1973 to 1975

Fraternities or Sororities

  • Phi Kappa Phi

Professional Associations

  • Iowa Bar Association, Member, 1975
  • American Bar Association, Member, 1975
  • Northwest Iowa Technical College Foundation, 1984
  • Sioux County Bar Association

Current Employment Positions