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IRS-authorized e-file provider · not the IRS

Nonprofit · EIN 47-4056866

WYNNE MATEFFY RESEARCH FOUNDATION

Tax-exempt · RCHO SANTA FE, CA 92067

Address and contacts

Address (IRS master file)
PO BOX 882, RCHO SANTA FE, CA 92067-0882
Mailing address (990-N for 2025)
PO Box 882, Rancho Santa Fe CA 92067
Principal officer (990-N for 2025)
Joshua Mateffy, PO Box 882, Rancho Santa Fe CA 92067
Website
wmrf.org

California records

California keeps its own records of charities and corporations. Search them by EIN 47-4056866 or by the name WYNNE MATEFFY RESEARCH FOUNDATION.

Attorney General, Registry of Charities and Fundraisers
Registration status and filed reports (CT-TR-1, RRF-1)

What it must file and when

IRS records say it files Form 990-N (e-Postcard). Gross receipts normally $50,000 or less. Its accounting year ends in December, so each return is due on the 15th day of the 5th month after that.

Tax yearYear endedDueIRS public records
2025December 31, 2025May 15, 2026990-N on file
2024December 31, 2024May 15, 2025990-N on file
2023December 31, 2023May 15, 2024990-N on file

File the 2026 990-N for WYNNE MATEFFY RESEARCH FOUNDATION

Due May 17, 2027 · e-filed with the IRS by 990.tax, an IRS-authorized e-file provider

IRS record

EIN
47-4056866
Tax-exempt status
501(c)(3): Charitable, religious, educational or scientific organization
Foundation status
Publicly supported organization (170(b)(1)(A)(vi))
Donations deductible (Pub 78)
Public charity, 50% deduction limit
Exempt since
2015
Accounting year ends
December
Files
Form 990-N (e-Postcard)
Category (NTEE)
Medical research (H12)

Filing history

FormYear endedRevenueExpensesAssetsReturn
990-N for 2025
Officer: Joshua Mateffy
December 31, 2025≤ $50,000 receipts––e-Postcard
990-N for 2024
Officer: Joshua Mateffy
December 31, 2024≤ $50,000 receipts––e-Postcard
990-N for 2023
Officer: Joshua Mateffy
December 31, 2023≤ $50,000 receipts––e-Postcard
990-N for 2022
Officer: Joshua Mateffy
December 31, 2022≤ $50,000 receipts––e-Postcard
990-N for 2020
Officer: JOSHUA MATEFFY
December 31, 2020≤ $50,000 receipts––e-Postcard
990-EZDecember 2018–––IRS
990December 2017–––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 47-4056866).

Questions about WYNNE MATEFFY RESEARCH FOUNDATION

What is the EIN of WYNNE MATEFFY RESEARCH FOUNDATION?
The employer identification number (EIN) of WYNNE MATEFFY RESEARCH FOUNDATION is 47-4056866.
Is WYNNE MATEFFY RESEARCH FOUNDATION tax-exempt?
Yes. The IRS lists it as tax-exempt under section 501(c)(3) since 2015.
Are donations to WYNNE MATEFFY RESEARCH FOUNDATION tax-deductible?
Yes. It is listed in IRS Publication 78 (Public charity, 50% deduction limit).
Which annual return does WYNNE MATEFFY RESEARCH FOUNDATION file?
Form 990-N (e-Postcard). Gross receipts normally $50,000 or less.
When is the next return of WYNNE MATEFFY RESEARCH 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 WYNNE MATEFFY RESEARCH FOUNDATION last file with the IRS?
The latest return in the IRS public files is the 990-N for 2025 for the year ended December 31, 2025.
Who is the principal officer of WYNNE MATEFFY RESEARCH FOUNDATION?
The 990-N for 2025 names Joshua Mateffy.

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