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Form 990-PFTax year 2025EIN 39-1597420

Sonnentag Foundation LTD

A private foundation in Marathon, WI. Its return for tax year 2025 reports $6.4 million paid in grants, listed in an attachment that is not in the e-file.

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Tax year 2025 (period ending Dec 31, 2025), read from the IRS e-file on Nov 11, 2026. Returns reach the IRS 5 to 18 months after the year they describe.

How to apply

Accepts applications

The return gives an application contact and rules, as below.

Contact
Carolyn Sonnentag
PO Box 435
Astatula, FL 34705
(715) 848-1365
Form and materials
Applications
Deadlines
None
Restrictions
Educational awards/local scholarships/religious needs/non-profit needs

Assets and giving by year

7 returns on file
Grants paid by tax year. The latest year is in blue.

  • Tax year 2025

    $6,371,389

    Grants listed
    In an attachment
    Assets, end of year
    $43,384,208

  • Tax year 2024

    $9,431,634

    Grants listed
    In an attachment
    Assets, end of year
    $45,256,271

  • Tax year 2023

    $1,178,234

    Grants listed
    1
    Assets, end of year
    $38,024,939

  • Tax year 2022

    $7,148,102

    Grants listed
    1
    Assets, end of year
    $32,746,874

  • Tax year 2021

    $653,714

    Grants listed
    1
    Assets, end of year
    $69,364,441

  • Tax year 2020

    $854,039

    Grants listed
    1
    Assets, end of year
    $56,867,665

  • Tax year 2019

    $2,922,435

    Grants listed
    1
    Assets, end of year
    $32,354,422

Grants paid in 2025

Grants listed in an attachment (not in the e-file)

As listed on the return.

  1. This return lists its grants in an attachment that is not in the IRS e-file: $6.4 million in all.

Officers, directors and trustees

3 people as filed

As filed on the return, with average hours per week and pay from the foundation.

  • John SonnentagPRESIDENT Hours 0Pay $0
  • Carolyn SonnentagVICE PRESIDENT PART TIME Hours 0Pay $0
  • Bill SonnentagDIRECTOR PART TIME Hours 0Pay $0

The return

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