Nonprofit · EIN 82-1801708
OPTIMIST INTERNATIONAL
Also known as 35234 HARRISBURG OC SOUTH DAKOTA
Tax-exempt · SIOUX FALLS, SD 57108
Address and contacts
- Address (IRS master file)
- 6506 S SANTA ROSA PL, SIOUX FALLS, SD 57108-2678
- In care of
- % ASHLEY LANGENSTEIN
- Mailing address (990-N for 2024)
- PO Box 93, Harrisburg SD 57032
- Principal officer (990-N for 2024)
- Theresa Langenstein, 506 Prairie St, Harrisburg SD 57032
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 September, so each return is due on the 15th day of the 5th month after that.
| Tax year | Year ended | Due | IRS public records |
|---|---|---|---|
| 2025 | September 30, 2026 | February 15, 2027 | Not due yet |
| 2024 | September 30, 2025 | February 16, 2026 | 990-N on file |
| 2023 | September 30, 2024 | February 17, 2025 | Check at the IRS |
IRS record
- EIN
- 82-1801708
- Tax-exempt status
- 501(c)(4): Social welfare organization
- Donations deductible
- No
- Exempt since
- 1958
- Accounting year ends
- September
- Files
- Form 990-N (e-Postcard)
- Group exemption
- 1334: OPTIMIST INTERNATIONAL
Filing history
| Form | Year ended | Revenue | Expenses | Assets | Return |
|---|---|---|---|---|---|
| 990-N for 2024 Officer: Theresa Langenstein | September 30, 2025 | ≤ $50,000 receipts | – | – | e-Postcard |
| 990-N for 2022 Officer: Todd Mundhenke | September 30, 2023 | ≤ $50,000 receipts | – | – | e-Postcard |
| 990-N for 2021 Officer: Todd Mundhenke | September 30, 2022 | ≤ $50,000 receipts | – | – | e-Postcard |
| 990-N for 2020 Officer: Kelly Casteel | September 30, 2021 | ≤ $50,000 receipts | – | – | e-Postcard |
| 990-N for 2018 Officer: Jennifer Walsh | September 30, 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 82-1801708).
Questions about OPTIMIST INTERNATIONAL
- What is the EIN of OPTIMIST INTERNATIONAL?
- The employer identification number (EIN) of OPTIMIST INTERNATIONAL is 82-1801708.
- Is OPTIMIST INTERNATIONAL tax-exempt?
- Yes. The IRS lists it as tax-exempt under section 501(c)(4) since 1958.
- Are donations to OPTIMIST INTERNATIONAL tax-deductible?
- No. The IRS master file says contributions to it are not deductible.
- Which annual return does OPTIMIST INTERNATIONAL file?
- Form 990-N (e-Postcard). Gross receipts normally $50,000 or less.
- When is the next return of OPTIMIST INTERNATIONAL due?
- The return for tax year 2025 (the year ending September 30, 2026) is due February 15, 2027. Form 8868 extends it by six months; the 990-N cannot be extended.
- When did OPTIMIST INTERNATIONAL last file with the IRS?
- The latest return in the IRS public files is the 990-N for 2024 for the year ended September 30, 2025.
- Who is the principal officer of OPTIMIST INTERNATIONAL?
- The 990-N for 2024 names Theresa Langenstein.
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