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Harold K. L. Castle Foundation


Last profile update: 04/13/2018
Last grant data update: 10/03/2017

At A Glance

Harold K. L. Castle Foundation

1197 Auloa Rd.

Kailua, HI United States 96734-4658

Telephone: (808) 263-7073


Type of Grantmaker

Independent foundation

Additional Descriptor






Incorporated in 1962 in HI - The foundation was founded by Harold K.L. Castle, a prominent landowner and community leader. Mr. Castle was the owner of Kaneohe Ranch and the land it occupied. He and his wife, Alice Hedemann Castle, were the major contributors to the foundation and were significant figures in the development of modern Hawaii. The land has been divided and sold over the years, but the foundation still owns some of the land and commercial properties as well as investments in stocks and bonds which provide the base from which the foundation's grants are given. The foundation, the largest private foundation based in Hawaii, awards a percentage of these assets each year to nonprofit organizations

Purpose and Activities

As the largest private foundation in the state of Hawaii, the foundation grants approximately $7,000,000 per year to organizations that serve Hawaii. The foundation is currently focusing on three strategic program areas: 1) Public Education Redesign and Enhancement; 2) Near-Shore Marine Resource Conservation; and 3) Windward Oahu.