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Nonprofit · EIN 52-2279668

CORNERSTONE INSTITUTE INC

Tax-exempt (reinstated) · ANNAPOLIS, MD 21401

Address and contacts

Address (IRS master file)
133 OLD SOLOMONS ISLAND RD, ANNAPOLIS, MD 21401-3825
In care of
% MARK C GOOD
Mailing address (990-N for 2025)
133 OLD SOLOMONS ISLAND RD, ANNAPOLIS MD 214013825
Principal officer (990-N for 2025)
Mark Good, 133 Old Solomons Island Rd, Annaplis MD 21401

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 CORNERSTONE INSTITUTE INC

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

IRS record

EIN
52-2279668
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
2015
Accounting year ends
December
Files
Form 990-N (e-Postcard)
Category (NTEE)
Education (B60)

Revocation and reinstatement

Exemption revoked
May 15, 2011
Posted by the IRS
February 22, 2012
Reinstated
Effective May 15, 2011

From the IRS automatic revocation list: organizations that did not file a required return or e-Postcard for three consecutive years.

Filing history

FormYear endedRevenueExpensesAssetsReturn
990-N for 2025
Officer: Mark Good
December 31, 2025≤ $50,000 receipts––e-Postcard
990-N for 2024
Officer: Mark Good
December 31, 2024≤ $50,000 receipts––e-Postcard
990-N for 2023
Officer: Mark Good
December 31, 2023≤ $50,000 receipts––e-Postcard
990-N for 2022
Officer: Mark Good
December 31, 2022≤ $50,000 receipts––e-Postcard
990-N for 2020
Officer: Mark Good
December 31, 2020≤ $50,000 receipts––e-Postcard
990-N for 2019
Officer: Mark Good
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 52-2279668).

Questions about CORNERSTONE INSTITUTE INC

What is the EIN of CORNERSTONE INSTITUTE INC?
The employer identification number (EIN) of CORNERSTONE INSTITUTE INC is 52-2279668.
Is CORNERSTONE INSTITUTE INC tax-exempt?
Yes. The IRS revoked its exemption on May 15, 2011 and reinstated it effective May 15, 2011.
Are donations to CORNERSTONE INSTITUTE INC tax-deductible?
Yes. It is listed in IRS Publication 78 (Public charity, 50% deduction limit).
Which annual return does CORNERSTONE INSTITUTE INC file?
Form 990-N (e-Postcard). Gross receipts normally $50,000 or less.
When is the next return of CORNERSTONE INSTITUTE 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 CORNERSTONE INSTITUTE 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 CORNERSTONE INSTITUTE INC?
The 990-N for 2025 names Mark Good.

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