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IRS-authorized e-file provider · not the IRS

Nonprofit · EIN 94-3326745

AMERICAN RIVER WATERSHED INSTITUTE

Also known as ARWI

Tax-exempt · AUBURN, CA 95603

Address and contacts

Address (IRS master file)
4135 EAGLES NEST, AUBURN, CA 95603-5923
In care of
% SIERRA BUSINESS SERVICES
Mailing address (990-N for 2025)
4135 Eagles Nest, Auburn CA 95603
Principal officer (990-N for 2025)
Otis Wollan, 23440 Milk Ranch Road, Colfax CA 95713

California records

California keeps its own records of charities and corporations. Search them by EIN 94-3326745 or by the name AMERICAN RIVER WATERSHED INSTITUTE.

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 AMERICAN RIVER WATERSHED INSTITUTE

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

IRS record

EIN
94-3326745
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
2001
Accounting year ends
December
Files
Form 990-N (e-Postcard)
Category (NTEE)
Environment (C600)

Filing history

FormYear endedRevenueExpensesAssetsReturn
990-N for 2025
Officer: Otis Wollan
December 31, 2025≤ $50,000 receipts––e-Postcard
990-N for 2024
Officer: GARY ESTES
December 31, 2024≤ $50,000 receipts––e-Postcard
990-N for 2023
Officer: GARY ESTES
December 31, 2023≤ $50,000 receipts––e-Postcard
990-N for 2022
Officer: T OTIS WOLLAN
December 31, 2022≤ $50,000 receipts––e-Postcard
990-N for 2020
Officer: T OTIS WOLLAN
December 31, 2020≤ $50,000 receipts––e-Postcard
990-N for 2019
Officer: Otis Wollan
December 31, 2019≤ $50,000 receipts––e-Postcard

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 94-3326745).

Questions about AMERICAN RIVER WATERSHED INSTITUTE

What is the EIN of AMERICAN RIVER WATERSHED INSTITUTE?
The employer identification number (EIN) of AMERICAN RIVER WATERSHED INSTITUTE is 94-3326745.
Is AMERICAN RIVER WATERSHED INSTITUTE tax-exempt?
Yes. The IRS lists it as tax-exempt under section 501(c)(3) since 2001.
Are donations to AMERICAN RIVER WATERSHED INSTITUTE tax-deductible?
Yes. It is listed in IRS Publication 78 (Public charity, 50% deduction limit).
Which annual return does AMERICAN RIVER WATERSHED INSTITUTE file?
Form 990-N (e-Postcard). Gross receipts normally $50,000 or less.
When is the next return of AMERICAN RIVER WATERSHED INSTITUTE 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 AMERICAN RIVER WATERSHED INSTITUTE 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 AMERICAN RIVER WATERSHED INSTITUTE?
The 990-N for 2025 names Otis Wollan.

Other nonprofits in AUBURN

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