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Samuel N & Mary Castle Fdn at a glance

· Private foundation

Samuel N & Mary Castle Fdn

Its FY2024 filing reports that it accepted unsolicited grant applications.

$1.9M
Granted FY2023
42
Grants FY2023
—
States reached
$134k
Largest
01What it fundsRead
02The needRead
03Its granteesRead
04Its fieldRead
05Through PlinthRead
01What it funds
0198% classified

What it funded, over time

Every grant placed by its stated purpose and the recipient’s mission, by year, FY2020 to 2024.

Education$4.0MHuman Services$2.1MPhilanthropy$429kHealth$376kCommunity Improvement$210kReligion$207kArts & Culture$164kSocial Science$147kOther$0
02FY2023 · 42 grants

Where the money goes

Grants by size, and the largest recipients.

How this is measured
The 42 grants below total $1,808,412, the rows itemized in this filing. The $1,853,412 headline is the total grant expense on the return; the other $45,000 is giving the schedule does not break out (grants under the $5,000 itemization floor, grants to individuals, grants on other schedules). Every figure below describes the itemized rows only.

By grant size · FY2023

  • $10k–50k23 grants · $489k
  • $50k–250k19 grants · $1.3M
$44,000
Median grant
—
States reached
$39M
Total assets
Largest grants
RecipientAmount
Erikson Institute$134,167
University of Hawaii Foundation$125,000
Hawaii Community Foundation$100,000
Punahou School$100,000
Hawaii Children's Action Network$75,000
Chaminade University of Honolulu$75,000
Child & Family Service$75,000
Kokua Kalihi Valley Comprehensive Family Services$60,000
Catholic Diocese of Honolulu$60,000
Chaminade University of Honolulu$60,000
Partners in Development Foundation$55,000
Maui Family Support Services$50,000
Family Hui Hawaii$50,000
Catholic Charities$50,000
PATCH (People Attentive to Children)$50,000
02The need
03

Does the money reach high-need areas?

Each grant placed by the hardship in its grantee’s ZIP, against the area’s typical level.

show:

Its human-services grants (FY20–22, $471k) land where the poverty rate runs at 9%, against an area that typically sits at 11%. 0% of those dollars go to grantees based in above-average-need neighborhoods. Its grants skew toward lower-need ZIPs.

area typical 11%CATHOLIC CHARITIES: $60k → 9%CATHOLIC CHARITIES: $60k → 9%CATHOLIC CHARITIES: $50k → 9%CATHOLIC CHARITIES: $50k → 9%NA KAMALI'I HOALOHA: $15k → 9%CATHOLIC CHARITIES: $50k → 9%NA KAMALI'I HOALOHA: $14k → 9%NA KAMALI'I HOALOHA: $12k → 9%NA KAMALI'I HOALOHA: $10k → 9%NA KAMALI'I HOALOHA: $10k → 9%WAIKIKI COMMUNITY CENTER: $50k → 9%WAIKIKI COMMUNITY CENTER: $15k → 9%WAIKIKI COMMUNITY CENTER: $15k → 9%WAIKIKI COMMUNITY CENTER: $10k → 9%YMCA OF HONOLULU: $50k → 9%0%20%40%50%more need →
grant to an above-average-need area below average· circle size = grant amount
How this is measured
Matched: human-services grants are those whose grantee’s IRS cause code is Human Services. Placed by people below the poverty line in the grantee’s ZIP, averaged from the tracts in that ZIP.
How this is measured
US grants placed by each grantee’s ZIP, which can differ from where services are delivered. Need from public data (U.S. Census/ACS, CDC PLACES, Eviction Lab, USDA), shown as context about the area, never attributed to the funder’s giving.
03Its grantees
repeat funding

Who it funds again

Organizations funded in more than one year, against those funded once.

66%of every dollar goes to organizations it has funded before.
$5.2M · 37 repeat orgs$2.7M to everyone else

Grantees it renews have grown median revenue +39% since the first grant, against +20% for those funded once.

37 repeat relationships: 7 still active in FY2023, 30 since wound down; 32 grantees were first funded in FY2023 (too recent to call).

How the two cohorts compare

Re-uppedFunded once

Organizations

37
32

Total granted

$5.2M
$1.1M

Median revenue growth · since first grant

+39%
+20%

Still filing today

76%
50%

New vs renewed · share of each year

In FY2023, 12% of grant dollars renewed an existing relationship; $1.6M went to new ones.

50%100%’20’21’22’23
RenewedFirst-time

Where new relationships form · theme of each grantee’s first grant

’20’21’22’23
EducationHuman ServicesHealthCommunity ImprovementArts & CultureMembership BenefitOther
How this is measured
First-time means a grantee’s first year in the filing window; renewed means funded in an earlier year too. The renewed share climbs naturally as a portfolio matures, so the signal is a year that bucks it (a wave of new grantees). The earliest year is left-censored: relationships that predate the data read as new. Theme is the grantee’s IRS cause.

Backed again, and grew

  • UO
    UNIVERSITY OF HAWAII FOUNDATION
    3× · 2020–2022 · $526k · revenue +132%
  • HC
    HAWAII CHILDREN'S ACTION NETWORK
    3× · 2020–2022 · $300k · revenue +275%
  • EI
    Erikson Institute
    2× · 2021–2022 · $278k · revenue +1%

Funded once

  • PS
    PUNAHOU SCHOOL
    one grant, 2022 · $100k · revenue +20%
  • DO
    DEPARTMENT OF EDUCATION
    one grant, 2022 · $100k
  • NL
    National Louis Universitygraduated
    one grant, 2021 · $88k · revenue +31%
How this is measured

Repeat means funded in two or more distinct years. Growth and survival are read from each grantee’s own subsequent IRS filings.

04Its field

Closest unfunded matches

The nonprofits that most resemble its grantees but are not funded by it, scored along the direction from the rest of the field toward the portfolio. A resemblance in what they say they do, not a recommendation.

1
Hawaii Education Institute
—
2
Kula Aupuni Niihau a Kahelelani Aloha (Kanaka)

Preserve niihau cultural values and language.

Education
3
Mohala Pua School Dba Honolulu Waldorf School

See schedule o.at honolulu waldorf school, we educate each child to find meaning, passion, and purpose in life and to contribute to the creation of a better world for all. through a curriculum based on the developmental stages of the human…

Education
4
Papahana Kuaola

Papahana kuaola's mission is to create quality educational programs focused on environmental restoration and economic sustainability fully integrated with hawaiian knowledge in order to exemplify a lifestyle respectful of kanaka, `aina,…

Environment
5
Waimea Country School

Waimea country school's mission is to educate children to become confident, responsible, and compassionate people.

Education
6
E Kupaku Ka Aina - the Hawaii Land Restoration Institute
Environment
7
Kapi'olani Medical Specialists

Kapi'olani medical specialists (dba hawai'i pacific health medical group) is a multispecialty provider group dedicated to providing world-class care for adults and children across hawai'i and the pacific region working in partnership with…

Health
8
'Iolani School

To develop educated, well-rounded individuals who are well prepared for college.

Education
9
Hawaii - American Nurses Association Foundation
Environment
10
Kanu O Ka Aina Learning Ohana

Serving and perpetuating sustainable hawaiian communities through education with aloha.

Arts & Culture
11
The Early School

Our mission is to provide young children in hawai'i experiences that cultivate their social, emotional, physical, and cognitive development through play, exploration, and connection.

Education
12
The Koloa Early School

To provide 3-4 year old with early childhood education

—
How this is measured
The grantee most central to the portfolio’s shape is Hanahauoli School; the most unlike its peers is Candid. Resemblance is measured on each organization’s own IRS 990 mission text; it reflects how work is described, not its quality or impact.
04the grantee network

45 grantees tracked through their own filings, 2017–2025.

Each grant beside the grantee’s revenue from every source, year by year.

How this is measured

Counted here: distinct organizations funded across 2017 to 2025, not grant rows in a single year, so this will not match the grant count on the cover. 45 of the 102 grantees resolved in that span have returns of their own we could reconcile.

Each grantee is resolved to its own IRS returns. Association, dated; never a causal claim.

0
Load-bearing (≥25% of a budget)
7
Early backer (in before they grew)
45/45
Grantees still filing
39/45
Grew since first funded

Where the money sits, by cause and then by grantee

CATHOLIC DIOCESE OF HONOLULU: $295,000 · OtherCATHOLIC DIOCESE OF HONOLULUThe Salvation Army: $240,000 · OtherThe Salvation ArmyCHILD AND FAMILY SERVICE: $225,000 · OtherMAUI FAMILY SUPPORT SERVICES INC: $195,000 · OtherFAMILY SUPPORT HAWAII: $190,000 · OtherYWCA OF HAWAII ISLAND: $170,000 · OtherChaminade University of Honolulu: $145,000 · Other+62 more: $2,826,630 · Other+62 moreUNIVERSITY OF HAWAII FOUNDATION: $526,224 · EducationUNIVERSITY OF HAWAII FOUNDATIONHAWAII CHILDREN'S ACTION NETWORK: $300,000 · EducationHAWAII CHILDREN'S ACTION NETWOR…Erikson Institute: $278,288 · EducationErikson InstituteCHAMINADE UNIVERSITY OF HONOLULU: $200,000 · EducationCHAMINADE UNIVERSITY OF HONOLUL…INSTITUTE FOR NATIVE PACIFIC EDUCATION AND CULTURE: $180,000 · EducationINSTITUTE FOR NATIVE PACIFIC ED…KCAA PRESCHOOLS OF HAWAII: $119,000 · EducationKCAA PRESCHOOLS OF HAWAIIPUNAHOU SCHOOL: $100,000 · EducationSEAGULL SCHOOLS INC: $90,000 · EducationNational Louis University: $87,840 · EducationHANALANI SCHOOLS: $75,000 · Education+8 more: $244,800 · Education+8 moreCATHOLIC CHARITIES HAWAII: $270,000 · Human ServicesWAIKIKI COMMUNITY CENTER: $90,000 · Human ServicesFAMILY HUI HAWAII: $75,000 · Human ServicesNA KAMALII HOALOHA: $61,480 · Human ServicesYOUNG MEN'S CHRISTIAN ASSOCIATION OF HONOLULU: $50,000 · Human ServicesIMUA FAMILY SERVICES: $200,000 · HealthPARENTS AND CHILDREN TOGETHER: $161,008 · HealthKOKUA KALIHI VALLEY COMPREHENSIVE FAMILY SERVICES: $60,000 · HealthKapi'olani Health Foundation: $50,000 · HealthPARTNERS IN DEVELOPMENT FOUNDATION: $160,000 · Community ImprovementTHIRD SECTOR NEW ENGLAND INC: $30,000 · Community ImprovementHAWAII ALLIANCE OF NONPROFIT ORGANIZATIONS: $20,114 · Community ImprovementCollaborative Support Services Inc: $175,000 · Membership BenefitHAWAII COMMUNITY FOUNDATION: $148,909 · Philanthropy+1 more: $5,000 · Philanthropy
Other$4,286,630Education$2,201,152Human Services$546,480Health$471,008Community Improvement$210,114Membership Benefit$175,000Philanthropy$153,909

Each grantee by its size and the funder’s share of it; top left is load-bearing

25%50%75%100%$1.0M$10M$100Mgrantee revenue →↑ funder's share of their budgetUNIVERSITY OF HAWAII FOUNDATION: $526,224 over 3y, 0.3% of budgetHAWAII CHILDREN'S ACTION NETWORK: $300,000 over 3y, 9.3% of budgetErikson Institute: $278,288 over 2y, 0.5% of budgetCATHOLIC CHARITIES HAWAII: $270,000 over 3y, 0.4% of budgetCHILD AND FAMILY SERVICE: $225,000 over 3y, 0.3% of budgetCHAMINADE UNIVERSITY OF HONOLULU: $200,000 over 3y, 0.1% of budgetIMUA FAMILY SERVICES: $200,000 over 3y, 1.6% of budgetMAUI FAMILY SUPPORT SERVICES INC: $195,000 over 3y, 1.5% of budgetINSTITUTE FOR NATIVE PACIFIC EDUCATION AND CULTURE: $180,000 over 3y, 1.5% of budgetCollaborative Support Services Inc: $175,000 over 3y, 3.8% of budgetYWCA OF HAWAII ISLAND: $170,000 over 3y, 3.5% of budgetPARENTS AND CHILDREN TOGETHER: $161,008 over 3y, 0.2% of budgetPARTNERS IN DEVELOPMENT FOUNDATION: $160,000 over 3y, 0.3% of budgetHAWAII COMMUNITY FOUNDATION: $148,909 over 2y, 0.1% of budgetRAINBOW SCHOOL: $120,000 over 3y, 2.0% of budgetKCAA PRESCHOOLS OF HAWAII: $119,000 over 3y, 1.0% of budgetPUNAHOU SCHOOL: $100,000 over 1y, 0.1% of budgetSEAGULL SCHOOLS INC: $90,000 over 3y, 0.7% of budgetWAIKIKI COMMUNITY CENTER: $90,000 over 3y, 2.7% of budgetNational Louis University: $87,840 over 1y, 0.1% of budgetHANAHAUOLI SCHOOL: $82,090 over 2y, 0.6% of budgetST ANDREW'S SCHOOLS: $75,000 over 1y, 0.7% of budgetHANALANI SCHOOLS: $75,000 over 3y, 0.3% of budgetFAMILY HUI HAWAII: $75,000 over 2y, 6.5% of budgetHAWAII FOODBANK INC: $65,000 over 2y, 0.1% of budgetFRIENDS OF THE FUTURE: $61,500 over 2y, 1.2% of budgetNA KAMALII HOALOHA: $61,480 over 3y, 6.9% of budgetKOKUA KALIHI VALLEY COMPREHENSIVE FAMILY SERVICES: $60,000 over 1y, 0.2% of budgetHUI NO'EAU: $51,000 over 3y, 1.7% of budgetKapi'olani Health Foundation: $50,000 over 1y, 0.4% of budgetYOUNG MEN'S CHRISTIAN ASSOCIATION OF HONOLULU: $50,000 over 1y, 0.2% of budgetKauai Christian Academy: $50,000 over 1y, 2.9% of budgetMONTESSORI OF MAUI INC: $50,000 over 1y, 1.0% of budgetALOHA SCHOOL EARLY LEARNING CENTER INC: $45,000 over 2y, 11% of budgetMONTESSORI COMMUNITY SCHOOL: $39,000 over 3y, 0.4% of budgetTHIRD SECTOR NEW ENGLAND INC: $30,000 over 1y, 0.0% of budgetHONOLULU THEATRE FOR YOUTH: $30,000 over 3y, 0.7% of budgetKEIKI O KA 'AINA PRESCHOOL INC: $25,800 over 1y, 0.2% of budgetFIRST UNITED METHODIST PRESCHOOL: $25,000 over 1y, 5.1% of budgetMAUI PREPARATORY ACADEMY: $25,000 over 1y, 0.3% of budgetHAWAII ALLIANCE OF NONPROFIT ORGANIZATIONS: $20,114 over 1y, 2.7% of budgetMAKUA LANI CHRISTIAN ACADEMY: $18,000 over 1y, 0.7% of budgetHAWAII ASSOCIATION OF INDEPENDENT SCHOOLS: $6,000 over 2y, 0.2% of budgetMANOA HERITAGE CENTER FKA MANOA VALLEY CULTURAL HERITAGE FOUND: $5,000 over 1y, 0.7% of budgetCANDID: $5,000 over 1y, 0.0% of budget
Grantee by grantee: a decade per organization, before and after funding

A decade per grantee: revenue shaded, grants as bars, all rows on one timeline.

  • Who funds UNIVERSITY OF HAWAII FOUNDATION ↗
  • Who funds HAWAII CHILDREN'S ACTION NETWORK ↗
  • Who funds Erikson Institute ↗
  • Who funds CATHOLIC CHARITIES HAWAII ↗
  • Who funds CHILD AND FAMILY SERVICE ↗
  • Who funds CHAMINADE UNIVERSITY OF HONOLULU ↗
  • Who funds IMUA FAMILY SERVICES ↗
  • Who funds MAUI FAMILY SUPPORT SERVICES INC ↗
  • Who funds INSTITUTE FOR NATIVE PACIFIC EDUCATION AND CULTURE ↗
  • Who funds Collaborative Support Services Inc ↗
  • Who funds YWCA OF HAWAII ISLAND ↗
  • Who funds PARENTS AND CHILDREN TOGETHER ↗
  • Who funds PARTNERS IN DEVELOPMENT FOUNDATION ↗
  • Who funds HAWAII COMMUNITY FOUNDATION ↗
  • Who funds RAINBOW SCHOOL ↗
  • Who funds KCAA PRESCHOOLS OF HAWAII ↗
  • Who funds PUNAHOU SCHOOL ↗
  • Who funds SEAGULL SCHOOLS INC ↗
  • Who funds WAIKIKI COMMUNITY CENTER ↗
  • Who funds National Louis University ↗
  • Who funds HANAHAUOLI SCHOOL ↗
  • Who funds ST ANDREW'S SCHOOLS ↗
  • Who funds HANALANI SCHOOLS ↗
  • Who funds FAMILY HUI HAWAII ↗
  • Who funds HAWAII FOODBANK INC ↗

Co-funders

Grantmakers whose grantees overlap with this funder’s far more than size alone predicts. Closer means stronger alignment; arcs show where they also fund each other. Here they form a tightly interlocked group: most of these funders back each other's grantees too.

Atherton Family Found…McInerny Foundation--Trustees of the Estat…Bank of Hawaii Charit…Tradewind Group Found…George N Wilcox Gener…Aloha United Way IncJ Watumull FundCentral Pacific Bank …Kosasa FoundationFirst Hawaiian Bank F…The Harry and Jeanett…
Atherton Family FoundationHI50× affinity22 shared granteesties to 11 of 11Hover any node to trace its alignments.Compare side by side →

Open a dossier: Atherton Family Foundation · McInerny Foundation-- · Trustees of the Estate of Bernice Pauahi Bishop Dba Kamehameha Schools · Bank of Hawaii Charitable Fdn · Tradewind Group Foundation · George N Wilcox General Trust · Aloha United Way Inc · J Watumull Fund · Central Pacific Bank Foundation · Kosasa Foundation · First Hawaiian Bank Foundation · The Harry and Jeanette Weinberg Foundation Inc

How this is measured
Affinity is a Gamma-Poisson posterior co-funding rate, re-centered on the typical rate, so thin evidence shrinks toward no signal. Overlap is association, not proof of shared intent.

How much its grantees rely on government

Each dot is one organization Samuel N & Mary Castle Fdn funds: left to right is the share of its income from government, bottom to top the share from Samuel N & Mary Castle Fdn. Bigger dots raise more.

2024
’20’21’22’23’24’25
no gov · 00%1%4%8%15%funder's share of their income ↑0%25%50%75%100%share of the org’s income from government →median 3%
  • Third Sector New England Inc: 3% of income from government
no gov moneyreceives it· size = income
0get no government money at all
12report government grants on their 990 we could not trace to a source (not plotted)
0rely on government for over half their income
typical government reliance, FY20–25
How this is measured
Government income is each org’s traced federal awards (USASpending grants and contracts) plus state payments (open checkbooks) as a share of its total revenue (IRS Form 990); the self-reported government-grant line (990 line 1e) is carried for cross-check: a grantee that reports government grants we could not trace to a source is left off the chart rather than shown as receiving none. An association, not a claim that a grant caused the public funding. Coverage is precision-first, a floor rather than a census; state records exist for 9 states, so a grantee outside them shows no state figure (dimmed) rather than a false zero. Federal award amounts are obligations, which can span years, so a single-year share is indicative. 990 filings lag 12 to 24 months.
05Through Plinth

Warm introductions · Powered by PlinthPlus

How do I get to Samuel N & Mary Castle Fdn?

Find your warmest path to Samuel N & Mary Castle Fdn through trustees and officers whose names appear on both boards. Search for your organization and Plinth traces the shortest route it can evidence.

Each link is a name appearing on two organizations’ public IRS 990 filings, matched on that name and, where the filings support it, on location. A same-state match has geographic support, which is a second matching feature rather than confirmation that the two are one person; a cross-state one is the likeliest to be two people who share a name. Every hop shows its tier, low-confidence and distant paths are held back rather than guessed, and it is worth confirming the person before you use the introduction.

On method. Every financial figure here is read from IRS e-file XML, the funder’s own 990/990-PF, and from the multi-year returns of the 102 grantees we resolved, each linked to its source. Grantee outcomes are each organization’s own program-service reporting (Form 990, Part III), read as association with funding, never as caused by it. Low-confidence name matches are suppressed rather than guessed. How we build these →

How this is measured
Each figure carries one of six labels. Filed is what the funder reported on its return. Official is another government record about an organization, such as a federal award or a charity register, joined by name where no shared identifier exists. Resolved is an identity we worked out where the filing named a recipient without an EIN, kept only above a measured confidence threshold. Computed is arithmetic over those, like themes, portfolio clusters and co-funder strength. Context is a statistic about a place rather than about an organization, which is what the need overlay is: it describes the area a grantee’s address sits in, not where its work lands. Inferred is drawn by a model from text, like the partnerships read out of public news and organization websites. Each is labeled where it appears.

Generated from the IRS Form 990-PF e-file return for fiscal year 2023, released 2023. Filings run roughly 12 to 24 months behind; figures are dated accordingly.

Possibly out of date. A more recent filing (FY2024) is on record and reports $1.9M of grant expense with no grantee named in the published copy. A private foundation itemizes every grant it makes, so a return carrying none has filed its list as an attachment that the public copy does not include. The figures above are therefore from FY2023, the most recent year this funder’s grantee list reached the public record.

Source object · view filing

Play a game based on Samuel N & Mary Castle Fdn’s filings →

More from the funding graph

The unnamed billions
grants reported with no recipient in the public record
The regranting layer
51% of grant dollars land in the regranting layer
The DAF merry-go-round
$9.7B circulates between donor-advised funds
The endowment market
who holds foundation money, and what just moved
The camps
funders cluster by geography, not ideology
By state
where grant money is based, and what stays home