The William C and Susan S Mariner
The William C and Susan S Mariner is a private foundation, based in Ocean City, MD. IRS filing data is available from 2020 through 2025. As of 2025, the organization holds $5.8M in total assets. In 2025, it awarded 2 grants totaling $12K.
The William C and Susan S Mariner at a glance
In short: The William C and Susan S Mariner gave $12K across 2 grants in 2025 (avg $6K), mostly in North Carolina. Source: 2025 IRS Form 990-PF.
- Annual giving (2025)
- $12,000
- +0.0% vs 2024
- Grants made (2025)
- 2
- +0.0% vs 2024
- Average grant
- $6,000
- +0.0% vs 2024
- Median grant
- $6,000
- Total assets
- $5,814,721
- +17.1% vs 2024
- Primary geography
- North Carolina (50% of itemized 2025 grant dollars)
- Latest 990 filing
- Form 990-PF, 2025 View filing
Data from IRS Form 990-PF, 2025; updated September 2026.
Who The William C and Susan S Mariner funds
How this funder distributes its grants
Top Recipients
Top 2 recipients in 2025
The largest 2025 recipient was Old Salem Inc-Mesda ($6K). Together the top 2 received $12K.
Grant Size Distribution
10 grants across all recorded years
The most common grant size was under $50K: 10 grants of 10 (100%).
Geographic Focus
Where this funder awards grants
Grant Distribution by State
Share of 2025 grant dollars across all 2 itemized grants.
States
Cities
How The William C and Susan S Mariner gives
- Giving grew 20% from 2022 to 2025. Method
- In 2025 it paid out well above its IRS minimum distribution (the 5% rule). Method
From the foundation's IRS Form 990-PF filings. Methodology.
Giving History
Giving Over Time
Total grant dollars and number of grants per year
From 2020 to 2025, annual grant giving ranged from $10K (2020) to $12K (2025). In 2025 it made 2 grants totaling $12K.
Grants by year
Grant recipients and amounts by year
| Recipient | Purpose | Amount |
|---|---|---|
| Old Salem Inc-Mesda Winston-Salem, NC | Summer Institute | $6,000 |
| The Decorative Arts Trust Media, PA | Summer Institute | $6,000 |
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Financial History
Multi-year comparison from IRS filings
| Filing year | Total Assets | Revenue | Expenses | Grants paid | Grants | Qualifying Distributions | Net Investment Income | Distributable Amount |
|---|---|---|---|---|---|---|---|---|
| 2025 | $5,814,721 | $859,900 | $12,000 | $12,000 | 2 | $12,000 | — | $51 |
| 2024 | $4,966,821 | $441,600 | $12,000 | $12,000 | 2 | $12,000 | — | $51 |
| 2023 | $4,537,221 | $3,153,474 | $10,000 | $10,000 | 2 | $10,000 | — | $51 |
| 2022 | $1,393,747 | $222,086 | $10,063 | $10,000 | 2 | $10,000 | — | $430 |
| 2021 | $1,181,724 | $645,072 | $10,072 | $10,000 | 2 | — | $4,510 | $3,039 |
| 2020 | $546,724 | $143,286 | $10,036 | $10,000 | 2 | — | $3,608 | $3,026 |
Under IRS private-foundation payout rules, The William C and Susan S Mariner reported a distributable amount of $51 for 2025 — the minimum it must pay out in qualifying distributions.
Leadership & Key People
Officers and directors from IRS filings
The William C and Susan S Mariner is led by William C. Mariner, President & Treasurer on every filing since 2020; none of the 2 officers listed in 2025 report compensation.
Officers on the 2025 filing
William C. Mariner
President & Treasurer
On filings since 2020
1 hr/week
No compensation reported
Susan S. Mariner
V.p. & Secretary
On filings since 2020
1 hr/week
No compensation reported
Data from IRS Form 990 filings, 2020–2025. "On filings since" is the earliest filing we hold that lists the person; hours are average hours per week as reported.
Frequently asked questions about The William C and Susan S Mariner
How much does The William C and Susan S Mariner give each year?
The William C and Susan S Mariner gave $12K across 2 grants in 2025, according to its 2025 IRS Form 990-PF. In 2024 it gave $12K across 2 grants.
How large is The William C and Susan S Mariner?
The William C and Susan S Mariner reported $5.8M in total assets on its 2025 IRS Form 990-PF. It paid out $12K in qualifying distributions that year, against a required minimum of $51 (roughly 5% of its investment assets).
Where does The William C and Susan S Mariner operate?
The William C and Susan S Mariner has awarded grants in North Carolina, Pennsylvania.
What is The William C and Susan S Mariner's EIN?
The William C and Susan S Mariner's EIN (Employer Identification Number) is 47-1925405. IRS Form 990 filing data is available on this page for 2020–2025.
Data last updated September 2026. Sourced from IRS Form 990-PF filings.
Data update history
(7)
When this profile's IRS filing data changed on Grantable
- Updated Form 990-PF for fiscal year 2020 (received by the IRS April 9, 2021)
- Updated Form 990-PF for fiscal year 2021 (received by the IRS April 12, 2022)
- Updated Form 990-PF for fiscal year 2022 (received by the IRS April 15, 2023)
- Updated Form 990-PF for fiscal year 2023 (received by the IRS April 10, 2024)
- Updated Form 990-PF for fiscal year 2024 (received by the IRS March 6, 2025)
- Updated Form 990-PF for fiscal year 2025 (received by the IRS April 11, 2026)
- IRS filings on file for fiscal years 2020–2025
Live grants for the work The William C and Susan S Mariner funds
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Figures come from The William C and Susan S Mariner's IRS filings (methodology). AI-written summaries, news items and logos are not covered by the open licence. Spot an error? Email hello@grantable.co.
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