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IRS-authorized e-file provider · not the IRS

Nonprofit · EIN 86-0381336

NATIONAL SPELEOLOGICAL SOCIETY INC

Also known as ESCABROSA GROTTA INC CHAPTER

Tax-exempt · TUCSON, AZ 85749

Address and contacts

Address (IRS master file)
8900 E BEARS PATH RD, TUCSON, AZ 85749-8139
Mailing address (990-N for 2025)
8900 E Bears Path Rd, TUCSON AZ 85749
Principal officer (990-N for 2025)
Mac Murray, 16642 W Calle Gravilla, Marana AZ 85653

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 NATIONAL SPELEOLOGICAL SOCIETY INC

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

IRS record

EIN
86-0381336
Tax-exempt status
501(c)(3): Charitable, religious, educational or scientific organization
Foundation status
Publicly supported organization (509(a)(2))
Donations deductible (Pub 78)
Public charity, 50% deduction limit
Exempt since
1980
Accounting year ends
December
Files
Form 990-N (e-Postcard)

Filing history

FormYear endedRevenueExpensesAssetsReturn
990-N for 2025
Officer: Mac Murray
December 31, 2025≤ $50,000 receipts––e-Postcard
990-N for 2024
Officer: Jerry W Isaman
December 31, 2024≤ $50,000 receipts––e-Postcard
990-N for 2023
Officer: Mac Murray
December 31, 2023≤ $50,000 receipts––e-Postcard
990-N for 2022
Officer: Jerry Isaman
December 31, 2022≤ $50,000 receipts––e-Postcard
990-N for 2020
Officer: Norman Ostensoe
December 31, 2020≤ $50,000 receipts––e-Postcard
990-N for 2019
Officer: Norman Ostensoe
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 86-0381336).

Questions about NATIONAL SPELEOLOGICAL SOCIETY INC

What is the EIN of NATIONAL SPELEOLOGICAL SOCIETY INC?
The employer identification number (EIN) of NATIONAL SPELEOLOGICAL SOCIETY INC is 86-0381336.
Is NATIONAL SPELEOLOGICAL SOCIETY INC tax-exempt?
Yes. The IRS lists it as tax-exempt under section 501(c)(3) since 1980.
Are donations to NATIONAL SPELEOLOGICAL SOCIETY INC tax-deductible?
Yes. It is listed in IRS Publication 78 (Public charity, 50% deduction limit).
Which annual return does NATIONAL SPELEOLOGICAL SOCIETY INC file?
Form 990-N (e-Postcard). Gross receipts normally $50,000 or less.
When is the next return of NATIONAL SPELEOLOGICAL SOCIETY INC 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 NATIONAL SPELEOLOGICAL SOCIETY INC 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 NATIONAL SPELEOLOGICAL SOCIETY INC?
The 990-N for 2025 names Mac Murray.

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