Nonprofit · EIN 04-6027800
TAMARACK FOUNDATION
Tax-exempt · BOSTON, MA 02110
Financials
| Year ended | Form | Revenue | Expenses | Net income | Total assets | Liabilities | Net assets |
|---|---|---|---|---|---|---|---|
| December 31, 2025 | 990-PF | $198,740 | $162,391 | $36,349 | $1,236,532 | $0 | $1,236,532 |
| December 31, 2024 | 990-PF | $558,500 | $160,661 | $397,839 | $1,200,184 | $0 | $1,200,184 |
| December 31, 2023 | 990-PF | $110,233 | $100,861 | $9,372 | $802,348 | $0 | $802,348 |
Financial details: 990-PF for the year ended December 31, 2025
Revenue
- Contributions, gifts and grants
- $171,348
- Dividends
- $22,264
- Interest
- $22
- Net gain from sales of assets
- $4,897
- Other income
- $209
Expenses
- Grants and similar amounts paid
- $143,700
- Compensation of officers, directors and key employees
- $0
- Disbursements for charitable purposes
- $149,520
- Excise tax on investment income
- $815
Balance sheet and other
- Total assets, start of year
- $1,200,184
- Total assets, end of year
- $1,236,532
- Total liabilities, end of year
- $0
- Net assets, end of year
- $1,236,532
- Fair market value of assets
- $1,427,636
- Qualifying distributions
- $149,520
- Net investment income
- $70,137
From the e-filed returns the IRS publishes as XML (latest three processing years; amended returns replace the original). PDF copies at the IRS.
Officers, directors and key employees
As listed on the 990-PF for the year ended December 31, 2025, highest compensation first.
| Name | Title | Hours / week | Compensation |
|---|---|---|---|
| WILLIAM H DARLING 21 CUSTOM HOUSE ST FL 5, BOSTON, MA 02110 | TRUSTEE | 1 | $0 |
| HENRY P PHIPPEN 21 CUSTOM HOUSE ST FL 5, BOSTON, MA 02110 | TRUSTEE | 2 | $0 |
990-PF for the year ended December 31, 2024: 2 people
| Name | Title | Hours / week | Compensation |
|---|---|---|---|
| WILLIAM H DARLING AGAWAM TRUST MGMT101 ARCH ST STE, 1000, BOSTON, MA 02110 | TRUSTEE | 1 | $0 |
| HENRY P PHIPPEN AGAWAM TRUST MGMT 101 ARCH ST STE, 1000, BOSTON, MA 02110 | TRUSTEE | 2 | $0 |
990-PF for the year ended December 31, 2023: 2 people
| Name | Title | Hours / week | Compensation |
|---|---|---|---|
| WILLIAM H DARLING AGAWAM TRUST MGMT101 ARCH ST STE, 1000, BOSTON, MA 02110 | TRUSTEE | 1 | $0 |
| HENRY P PHIPPEN AGAWAM TRUST MGMT 101 ARCH ST STE, 1000, BOSTON, MA 02110 | TRUSTEE | 2 | $0 |
Address and contacts
- Address (IRS master file)
- 21 CUSTOM HOUSE ST FL 5, BOSTON, MA 02110-3507
- In care of
- % SAGAMORE TAX GROUP
- Signed the 990-PF
- HENRY P PHIPPEN, TRUSTEE
- Phone
- (617) 227-0600
- Return prepared by
- WOODSTOCK SERVICES COMPANY LLC
What it must file and when
IRS records say it files Form 990-PF. Private foundations file every year. Its accounting year ends in December, so each return is due on the 15th day of the 5th month after that.
| Tax year | Year ended | Due | IRS public records |
|---|---|---|---|
| 2025 | December 31, 2025 | May 15, 2026 | 990-PF on file |
| 2024 | December 31, 2024 | May 15, 2025 | 990-PF on file |
| 2023 | December 31, 2023 | May 15, 2024 | 990-PF on file |
IRS record
- EIN
- 04-6027800
- Tax-exempt status
- 501(c)(3): Charitable, religious, educational or scientific organization
- Foundation status
- Private non-operating foundation
- Donations deductible (Pub 78)
- Private foundation, 30% limit
- Exempt since
- 1960
- Accounting year ends
- December
- Files
- Form 990-PF
- Assets (IRS master file)
- $1,236,532
- Income (IRS master file)
- $279,926
Filing history
| Form | Year ended | Revenue | Expenses | Assets | Return |
|---|---|---|---|---|---|
| 990-PF | December 2025 | $198,740 | $162,391 | $1,236,532 | IRS |
| 990-PF | December 2024 | $558,500 | $160,661 | $1,200,184 | IRS |
| 990-PF | December 2023 | $110,233 | $100,861 | $802,348 | XML |
| 990-PF | December 2022 | – | – | – | IRS |
| 990-PF | December 2021 | – | – | – | IRS |
| 990-PF | December 2020 | – | – | – | IRS |
| 990-PF | December 2018 | – | – | – | IRS |
990-N: the IRS bulk file holds only the latest e-Postcard per organization; earlier years come from archived copies of that file since 2020 and can have gaps (the IRS e-Postcard search lists every one). 990, 990-EZ, 990-PF, 990-T: every e-filed return in the IRS e-file index since 2019; XML for the latest three processing years, amounts from the IRS Statistics of Income extracts before that. PDF copies and determination letters at the IRS (search EIN 04-6027800).
Questions about TAMARACK FOUNDATION
- What is the EIN of TAMARACK FOUNDATION?
- The employer identification number (EIN) of TAMARACK FOUNDATION is 04-6027800.
- Is TAMARACK FOUNDATION tax-exempt?
- Yes. The IRS lists it as tax-exempt under section 501(c)(3) since 1960.
- Are donations to TAMARACK FOUNDATION tax-deductible?
- Yes. It is listed in IRS Publication 78 (Private foundation, 30% limit).
- Which annual return does TAMARACK FOUNDATION file?
- Form 990-PF. Private foundations file every year.
- When is the next return of TAMARACK FOUNDATION due?
- The return for tax year 2026 (the year ending December 31, 2026) is due May 17, 2027. Form 8868 extends it by six months; the 990-N cannot be extended.
- When did TAMARACK FOUNDATION last file with the IRS?
- The latest return in the IRS public files is the 990-PF for the year ended December 2025.
- Who are the officers and directors of TAMARACK FOUNDATION?
- The 990-PF for the year ended December 31, 2025 lists 2 people; 0 received compensation from the organization.
- How much revenue does TAMARACK FOUNDATION have?
- On its 990-PF for the year ended December 31, 2025 it reported revenue of $198,740, expenses of $162,391 and total assets of $1,236,532 at year end.
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