Winiarski Family Foundation

Private foundation · EIN 26-0474242 · since 2007warrenwiniarski.com/philanthropy-1·California, District of Columbia, New Mexico·Updated 13 October 2026

At a glance

$43.1M

Annual giving, 2025 tax year

From the Form 990-PF filing

$5,000 to $3.1M

Grant range

From grants in the 990-PF filings

$3.1M

Typical grant (median)

3 grants in the latest filing

Invitation only

Unsolicited applications are not accepted

This funder does not accept unsolicited applications. The foundation chooses the organisations it funds itself.

Key takeaways

The foundation says its contributions go only to organisations it has preselected, and it does not accept unsolicited requests, so a small charity should not send it a cold proposal.
Its stated themes are conservation and preservation, and its website also records support for institutional work on wine and food history, so a charity should check whether its work sits in one of these areas.
Most of its grants are modest: half of its grants to organisations were $20,000 or less, and about 8 in 10 fall between $5,000 and $3,150,000, though this band is typical rather than a ceiling, since its largest grant was $37,500,000.
Relationships matter: the filing shows that 100% of its grant dollars to organisations went to organisations it had already funded in earlier filings, so a charity's best route is to be known to the foundation before asking.
No geographic focus is stated, so location should not be treated as a rule for who may apply.

Overview

Winiarski Family Foundation is a US private foundation based in Yountville, CA.

What they fund

Profile derived from the foundation's IRS Form 990-PF filings (TY2025, TY2024, TY2023) and its website, with every statement checked against those sources. Sources read on 12 October 2026.

Priority Areas

The Foundation describes giving to conservation and preservation efforts. Its philanthropy page also records support for institutional work on wine and food history, including research, collections, programmes and public events. In its filed grants, most awards are recorded as financial support for organisations rather than tied to a stated project purpose. Recipients include colleges and universities, cultural institutions, a medical centre, local community organisations, environmental and wildlife groups, and national organisations. The filing indicates that contributions go only to preselected charitable organisations and unsolicited requests are not accepted.

Themes

Conservation and preservation

Geographic Focus

No geographic focus is stated; the filings show grants mainly in New Mexico, California and District of Columbia.

How to apply

Contributions go only to preselected charitable organisations; unsolicited requests are not accepted.

Application success factors

Repeat giving: In its TY2025 filing, 100% of its grant dollars to organisations went to organisations it had also funded in its TY2023 or TY2024 filing.
Grant size: Across its TY2023, TY2024 and TY2025 filings, half of its 37 grants to organisations were $20,000 or less.

Where grants go

From grants to organisations in the foundation’s filings for tax years 2023–2025.

Grant dollars by state

New Mexico82%

California13%

District of Columbia5%

New York<1%

Colorado<1%

Maryland<1%

4 other states: <1%

The largest single recipient received 82% of grant dollars to organisations.
In tax year 2025, 100% of grant dollars went to organisations Winiarski Family Foundation had funded in earlier filings.
No grants were paid directly to organisations outside the US.

Grants

3 grants in the latest filing analysed · median $3.1M

The largest grants to organisations in the foundation’s latest filing:

ST Johns College · Financial support for the organization
$37,500,0002025 tax year
Smithsonian Institution · Financial support for the organization
$3,121,6142025 tax year
Uc Davis Foundation · Financial support for the organization
$2,446,0872025 tax year

Grants to organisations listed in the foundation’s Form 990-PF filings. Grants to individuals are not shown.

Officers and directors

Thomas Suniville — CFO / Director
Stacy Madigan — Secretary / Director
Greg Bennett — President / Director

From the latest Form 990-PF filing

3 years of tax filings

Year	Total expenses	Grants paid	Assets	Filing document
2023 tax year	$4,148,275	$3,970,514	$14,766,656	Filing for 2023 tax year
2024 tax year	$14,291,128	$14,206,820	$1,803,226	Filing for 2024 tax year
2025 tax year	$43,104,918	$43,067,701	$1,658,682	Filing for 2025 tax year

Figures from the foundation’s IRS Form 990-PF filings. Assets are at fair market value at year end. The document icon links to each year’s filing on ProPublica Nonprofit Explorer.