Mammoth Hospital Foundation
Promotion of medical, hospital and healthcare services throughout Mono and Inyo counties within the Eastern Sierra Nevada region, California. Provide assistance to people in need of Health Care as well as funds for advancements in facilities, technologies and programs.
Mammoth Hospital Foundation at a glance
In short: Mammoth Hospital Foundation gave $1.0M across 1 grant in 2025 (avg $1.0M), mostly in California. Source: 2025 IRS Form 990.
- Annual giving (2025)
- $1,024,126
- +250.6% vs 2024
- Grants made (2025)
- 1
- +0.0% vs 2024
- Average grant
- $1,024,126
- +250.6% vs 2024
- Median grant
- $1,024,126
- Total assets
- $1,898,527
- +81.8% vs 2024
- Primary geography
- California (100% of itemized 2025 grant dollars)
- Latest 990 filing
- Form 990, 2025 View filing
Data from IRS Form 990, 2025; updated September 2026.
Who Mammoth Hospital Foundation funds
How this funder distributes its grants
Top Recipients
Top recipient in 2025
The largest 2025 recipient was Mammoth Hospital ($1.0M).
Grant Size Distribution
5 grants across all recorded years
The most common grant size was in the $250–500K range: 2 grants of 5 (40%).
Geographic Focus
Where this funder awards grants
Grant Distribution by State
Share of the 2025 grant dollars on its one itemized grant.
States
Cities
How Mammoth Hospital Foundation gives
- Giving grew 856% from 2022 to 2025. Method
From the foundation's IRS Form 990 filings. Methodology.
Giving History
Giving Over Time
Total grant dollars and number of grants per year
From 2019 to 2025, annual grant giving ranged from $37K (2021) to $1.0M (2025). In 2025 it made 1 grant totaling $1.0M.
Grants by year
Grant recipients and amounts by year
| Recipient | Purpose | Amount |
|---|---|---|
| Mammoth Hospital Mammoth Lakes, CA | Auxiliary Capital Outlay | $1,024,126 |
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Financial History
Multi-year comparison from IRS filings
| Filing year | Total Assets | Revenue | Expenses | Grants paid | Grants | Net Investment Income |
|---|---|---|---|---|---|---|
| 2025 | $1,898,527 | $2,342,853 | $1,492,666 | $1,024,126 | 1 | $39,410 |
| 2024 | $1,044,122 | $998,110 | $637,111 | $292,083 | 1 | $53 |
| 2023 | $669,621 | $735,196 | $577,734 | $403,144 | 1 | — |
| 2022 | $436,159 | $430,723 | $193,939 | $107,105 | 1 | — |
| 2021 | $199,375 | $43,337 | $40,311 | $36,983 | 1 | — |
| 2020 | $196,349 | $85,567 | $105,286 | $101,915 | 1 | — |
| 2019 | $216,068 | $164,600 | $266,015 | $262,750 | 1 | — |
About Mammoth Hospital Foundation
Based on IRS filings
Mammoth Hospital Foundation is a public charity focused on Health, based in Mammoth Lakes, CA. IRS filing data is available from 2019 through 2025. As of 2025, the organization holds $1.9M in total assets. In 2025, it awarded 1 grant totaling $1.0M. Net investment income was $39K.
Focus Areas
Leadership & Key People
Officers and directors from IRS filings
Mammoth Hospital Foundation is led by Gardiner Miller, Executive Director on every filing since 2023; 1 of 7 officers listed in 2025 is compensated.
Officers on the 2025 filing
Gardiner Miller
Executive Director
On filings since 2023
1 hr/week
$141K (2025)
Gary Myer
Chair
Board Chair → Chair, 2024
On filings since 2020
4 hrs/week
No compensation reported
Carolyn Escoto
Treasurer
Vice Chair → Treasurer, 2020
On filings since 2019
1 hr/week
No compensation reported
Robert Amonic
Secretary
On filings since 2019
1 hr/week
No compensation reported
Eric Clark
Member at Large
On filings since 2021
1 hr/week
No compensation reported
Lorrie Gould
Member at Large
On filings since 2024
1 hr/week
No compensation reported
Timothy Crall
Vice Chair
On filings since 2024
1 hr/week
No compensation reported
Former officers (4)
- Former: Lotetta Gould (2021–2023) — Member at Large
- Former: Tim Crall (2023) — Vice Chair
- Former: Kyle Howell MD (2019–2022) — Vice Chair
- Former: Tracey Harrell (2019) — Treasurer
Data from IRS Form 990 filings, 2019–2025. "On filings since" is the earliest filing we hold that lists the person; hours are average hours per week as reported.
Compensation Overview
From 2025 IRS filing
The highest reported compensation on the 2025 filing was $141K, to Gardiner Miller (Executive Director).
Frequently asked questions about Mammoth Hospital Foundation
How much does Mammoth Hospital Foundation give each year?
Mammoth Hospital Foundation gave $1.0M across 1 grant in 2025, according to its 2025 IRS Form 990. In 2024 it gave $292K across 1 grant.
How large is Mammoth Hospital Foundation?
Mammoth Hospital Foundation reported $1.9M in total assets on its 2025 IRS Form 990. Its revenue that year was $2.3M.
What is Mammoth Hospital Foundation?
Mammoth Hospital Foundation is a public charity focused on Health, based in Mammoth Lakes, CA. It holds $1.9M in total assets as of 2025.
Where does Mammoth Hospital Foundation operate?
Mammoth Hospital Foundation has awarded grants in California.
What is Mammoth Hospital Foundation's EIN?
Mammoth Hospital Foundation's EIN (Employer Identification Number) is 20-2601653. IRS Form 990 filing data is available on this page for 2019–2025.
Data last updated September 2026. Sourced from IRS Form 990 filings.
Data update history
(8)
When this profile's IRS filing data changed on Grantable
- Updated Form 990 for fiscal year 2020 (received by the IRS February 19, 2021)
- Updated Form 990 for fiscal year 2021 (received by the IRS November 15, 2021)
- Updated Form 990 for fiscal year 2022 (received by the IRS February 6, 2023)
- Updated Form 990 for fiscal year 2024 (received by the IRS April 30, 2025)
- Added Form 990 for fiscal year 2019 (received by the IRS March 9, 2020)
- Updated Form 990 for fiscal year 2023 (received by the IRS January 28, 2025)
- Added Form 990 for fiscal year 2025 (received by the IRS May 15, 2026)
- IRS filings on file for fiscal years 2020–2024
Live grants for the work Mammoth Hospital Foundation funds
Health Open opportunities, soonest deadline first.
Explore Open Grants
Browse active grant opportunities in Mammoth Hospital Foundation's focus areas in our free grants database
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Figures come from Mammoth Hospital Foundation'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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