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Mammoth Hospital Auxiliary Inc

EIN 95-3141984 · Mammoth Lakes, CA

Public records show a registered, tax-exempt organization in good standing.

LegitimacyPassesRegistration and standingFinancial healthGood81 out of 100GovernanceStrong91 out of 100Impact evidenceDescribes programsHow well its results are evidenced

What it says it does

To provide support for the medical needs of the community of Mammoth Lakes which includes grants for the purchase of Mammoth Hospital equipment, promoting good healthcare in the hospital and community, and sponsoring medically related education.

Income
$428,491
Spending
$411,774
Spent on programs
61%
Reserves
8 months of spending
Largest source of income
donations and private grants, 99%
Employees
0
Volunteers
135

Source: Form 990 for the year ending June 30, 2025, filed with the Internal Revenue Service. Rating method 2026.2. How we rate

Financial health

Good: 81 out of 100. Higher than 54% of charities in its peer group (health care, $250k to $1m).

  • Reserves

    28 of 35

    Spendable reserves would cover 8.0 months of spending.

  • Debt

    20 of 20

    It owes 0% of what it owns.

  • Living within its means

    15 of 15

    Income exceeded spending by 4% of income.

  • Income trend

    10 of 15

    Income fell 10% on the year before.

  • Spending floor

    8 of 15

    61% of spending went to programs and raising each dollar of donations cost 25 cents.

Source: Form 990 for the year ending June 30, 2025, filed with the Internal Revenue Service. Rating method 2026.2. How we rate

Governance

Strong: 91 out of 100. Higher than 72% of charities in its peer group (health care, $250k to $1m).

  • Independent board

    25 of 25

    10 of 10 voting board members are independent.

  • Conflict of interest policy

    15 of 15

    Has a written conflict of interest policy.

  • Whistleblower policy

    8 of 8

    Has a written whistleblower policy.

  • Record keeping policy

    7 of 7

    Has a written policy on keeping and destroying records.

  • Board minutes

    5 of 5

    Keeps minutes of board meetings.

  • Board sees the tax return

    10 of 10

    Gave the board a copy of this return before filing it.

  • Independent check of accounts

    6 of 15

    Its accounts were not audited or reviewed by an independent accountant.

  • No reported misuse

    10 of 10

    Reports no diversion of assets, excess benefits or loans to insiders.

Source: Form 990 for the year ending June 30, 2025, filed with the Internal Revenue Service. Rating method 2026.2. How we rate

Impact evidence

Describes programs. Its tax return describes what it does but we have found no measurable results in it.

Programs described in its return (8)
  1. $201,072 spent. Purchase hospital equipment for the Mammoth Hospital based upon their requested needs.
  2. $20,000 spent. Provide continuing education for hospital employees, either as in-house training for staff based upon hospital approved programs or for reimbursed costs for attending continuing education courses.
  3. $14,000 spent. Provide (6) college scholarships: (1) for $5,000, (1) for $3,500, (1) for $2,000, (1) for $1,500 and (2) for $1,000 each for students enrolled in medical field courses and maintaining a high GPA.
  4. $8,757 spent. Support Mammoth Hospital Cancer Outreach Program for local resident travel expenses to treatment facilities outside Eastern Sierra. Advertise Blood Drive In Association with Mammoth Hospital.
  5. $5,100 spent. Provide High School seniors with achievement awards of $125 to $250 each.
  6. $1,493 spent. Membership appreciation officer installation, banguets, and newsletters. Also service awards are presented related to the approximately 10,000 plus hours donated by the volunteers.
  7. $500 spent. Co-Sponsor with Mammoth Community Hospital Community Health Programs. Rhiannons Kids Fund to provide financial support to families who must take their child out of Mammoth Lakes to access needed medical services.
  8. Baby Welcome Program, provided 100 infant onesies for new borns.

Source: Form 990 for the year ending June 30, 2025, filed with the Internal Revenue Service. Rating method 2026.2. How we rate

Legitimacy checks

  1. Is it registered with the IRS? Passed.

    Listed in the IRS master file of tax-exempt organizations as a 501(c)(3) charitable organization.

    Source: Exempt Organizations Business Master File, Internal Revenue Service, file dated October 13, 2026.

  2. Has the IRS revoked its tax-exempt status? Passed.

    Not on the IRS automatic revocation list.

    Source: Automatic revocation of exemption list, Internal Revenue Service, file dated October 13, 2026.

  3. Are donations tax-deductible? Passed.

    On the IRS list of organizations eligible to receive tax-deductible contributions.

    Source: Publication 78 data: organizations eligible for tax-deductible contributions, Internal Revenue Service, file dated October 13, 2026.

  4. Is it keeping up with its IRS filings? Passed.

    Most recent return on file covers the year ending June 2025.

    Source: Exempt Organizations Business Master File, Internal Revenue Service, file dated October 13, 2026.

  5. How long has it been tax-exempt? Passed.

    Recognized by the IRS since January 1978.

    Source: Exempt Organizations Business Master File, Internal Revenue Service, file dated October 13, 2026.

  6. Is it in good standing with state regulators? Passed.

    Not on California's list of charities barred from soliciting. Other states are not yet checked.

    Source: May Not Operate or Solicit for Charitable Purposes list, California Attorney General, Registry of Charities and Fundraisers, file dated October 21, 2026.

Ratings and checks are our reading of public records, using the published method. They are not a statement about anyone's honesty. If you work for this organization, you can send corrections or results, confirm you want gifts through Veridonate, or ask to be removed from giving.