Harold Kl Castle Foundation
The Harold K.L. Castle Foundation is one of the largest private foundations headquartered in Hawaii. Established in 1962 by Harold Kainalu Long Castle, owner of Kaneohe Ranch and descendant of one of Hawaii's early missionary families, the foundation works to build resources for Hawaii's future through strategic grantmaking, convening power, and the introduction of new ideas and approaches to address pressing problems in the state.
Financial Overview
From 2024 IRS Form 990-PF · View filing
Total Assets
$171.3M
-1.3% YoY
Annual Giving
$6.9M
-8.0% YoY
Grant Count
106
-4.5% YoY
Avg Grant Size
$65K
-3.7% YoY
Mission & Focus Areas
The foundation's 2025 mission and strategies focus on five key areas:
Public Education Redesign & Enhancement — Close the achievement gap in public education so that all of Hawaii's children and young adults, regardless of socioeconomic background, have access to and benefit from high-quality education from prekindergarten through college that prepares them for a successful future.
Nearshore Marine Resource Conservation — Restore Hawaii's nearshore ocean areas so that current and future generations can benefit and learn from this rich natural resource.
Strengthening Ko'olau O'ahu Communities — Build on the strengths of Ko'olau O'ahu communities through support of the region's rich cultural legacy, its people, and its natural resources.
Climate Resiliency — Strengthen communities' ability to adapt to the effects of climate change.
Other Compelling Opportunities — Support a limited number of unforeseen but compelling opportunities to make a significant difference in Hawaii's future.
The foundation views grants as investments in ambitious, creative initiatives that deliver measurable results and clearly make Hawaii a better place for its children, communities, and environment.
Grantmaking
Grant Range
$150,000 to $700,000
Average Grant
$110,000
How to Apply
**
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Geographic Focus
Where this funder awards grants
The foundation focuses exclusively on Hawaii, with particular priority on O'ahu and especially Windward O'ahu. Since 2000, the foundation has granted more than $60 million, with over $50 million directed to organizations serving Windward O'ahu.
Grant Distribution by State
Cities
Financial History
Multi-year comparison from IRS filings
Assets:
- $173.5 million (2024)
- $173 million (2023)
- $171.3 million (2024)
Annual Revenue & Expenses:
- Total revenues: $8,283,293 (2024)
- Total expenses: $10,627,064 (2024)
- Annual revenue: $5.3 million (alternate source)
Staffing:
- 7 employees (2024)
- 6 employees (alternate source)
| Metric | 2024 | 2023 | 2022 |
|---|---|---|---|
| Total Assets | $171,295,453 | $173,491,448 | $173,044,264 |
| Revenue | $8,283,293 | $11,327,617 | $8,125,647 |
| Expenses | $10,627,064 | $10,879,744 | $11,246,442 |
| Qualifying Distributions | $8,758,237 | $9,503,881 | $9,746,584 |
| Net Investment Income | $7,046,551 | $10,105,204 | $6,568,148 |
| Distributable Amount | $9,515,391 | $8,920,185 | $9,315,597 |
Giving Over Time
Total grant dollars and number of grants per year
Grant Insights
How this funder distributes its grants
Top Recipients
Top 10 recipients in 2024
Grant Size Distribution
250 grants across all recorded years
Open Grants
5 open opportunities from Harold Kl Castle Foundation
Ko'olau Pilina Fund Grant
HAROLD KL CASTLE FOUNDATION
Amount
US $3,000 - US $15,000
Deadline
Rolling / Open
Nearshore Marine Resource Conservation Grant
HAROLD KL CASTLE FOUNDATION
Amount
US $100 - US $4,000,000
Deadline
Rolling / Open
Post-Secondary Transition RFP
HAROLD KL CASTLE FOUNDATION
Amount
Varies
Deadline
Rolling / Open
Giving History
Grant recipients and amounts by year
No grants recorded for .
Leadership & Key People
Leadership team and compensation from IRS filings
- Terrence George — President and Chief Executive Officer (retiring in 2025 after 22 years of service)
- Alex Harris — President (as of 2025, overseeing grantmaking, strategy, and impact)
- Eric Co — Chief Executive Officer (as of 2025, managing operations)
- Corbett Kalama — Director
- James McIntosh — Director
- Beth Murph — Grants Manager
Compensation Overview
From 2024 IRS filing
From 2024 filing
| Name | Title | Hours | Compensation |
|---|---|---|---|
| HENRY M D'OLIER | DIRECTOR/CHAIRMAN | 2 | — |
| DR CLAIRE L ASAM | DIRECTOR | 0.5 | — |
| DR KITTREDGE A BALDWIN | DIRECTOR | 0.5 | — |
| CORBETT AK KALAMA | DIRECTOR | 0.5 | — |
| DEE JAY A MAILER | DIRECTOR | 0.5 | — |
| JAMES H MCINTOSH | DIRECTOR | 0.5 | — |
| JENNIFER G SABAS | DIRECTOR | 0.5 | — |
| T AULANI WILHELM | DIRECTOR | 0.5 | — |
| ERIC K YEAMAN | DIRECTOR | 0.5 | — |
| CARLTON KC AU | VICE PRESIDENT OF FINANCE | 8 | $55,473 |
| DENNIS ERIC CO | VICE PRESIDENT OF RESILIENCY | 40 | $222,888 |
| TERRENCE R GEORGE | PRESIDENT/CEO | 40 | $414,566 |
| ALEXANDER HARRIS | VICE PRESIDENT OF PROGRAMS | 40 | $221,541 |
| ANN S MATSUKADO | TREASURER | 40 | $189,023 |
| SUSAN L SUMIDA | SECRETARY | 5 | $27,799 |
Recent News & Activity
Recent developments and announcements
Hawaii's first-ever Youth Apprenticeship in creative media launched with a $200,000 grant from the foundation (2026)
Hawai\u02BBi's first-ever Youth Apprenticeship in creative media ...The foundation and Kamehameha Schools granted $2.1 million to Windward Community College
The Harold K.L. Castle Foundation and KS grant $2.1 million to Windward CommunityThe foundation is accepting grant applications through the Ko'olau Pilina Fund
Ko\u02BBolau Pilina Fund Accepting Grant ApplicationsLeadership transition underway in 2025, moving from single CEO model to co-leadership structure with separate President and CEO roles
Contact Information
Address: 1197 Auloa Road, Kailua, HI 96734
Phone: 808-263-7073
Fax: 808-261-6918
Website: castlefoundation.org
Email: info@castlefoundation.org
Data last updated April 2026. Sourced from IRS Form 990-PF filings. Research dossier generated April 2026.
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