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Winslow Foundation

Annual Giving
$1.9M
Grant Range
$1K - $0.3M

Quick Stats

  • Annual Giving: $1.7-2.1 million
  • Success Rate: N/A (invitation-only)
  • Decision Time: Not publicly disclosed
  • Grant Range: $500 - $250,000
  • Geographic Focus: National (priority on CA, NY, MA, CO)

Contact Details

  • Website: None (maintains low public profile)
  • Phone: (800) 839-1754
  • Email: Not publicly available
  • Address: c/o Foundation Source, 501 Silverside Road, Wilmington, DE 19809

Overview

The Winslow Foundation is a private family foundation established in 1987 by Wren Winslow Wirth, with total assets of approximately $30 million as of 2024. The foundation distributes between $1.7-2.1 million annually to support environmental conservation, clean energy initiatives, and women's reproductive health organizations. Operating with a deliberately low public profile and no website, the foundation maintains an invitation-only grant-making approach, working primarily with preselected organizations with whom they have established relationships. The foundation is managed by a small family board including founder Wren Winslow Wirth as President, her children Christopher and Kelsey Wirth as trustees, and notable board member Teresa Heinz Kerry.

Funding Priorities

Grant Programs

The foundation does not operate formal grant programs but provides flexible general support and project-specific funding:

  • General Operating Support: $10,000 - $250,000 (for established partners)
  • Project Support: $500 - $100,000 (for specific initiatives)
  • Multi-year commitments available for strategic partners

Priority Areas

Primary Focus (70% of grants):

  • Environmental conservation and climate action
  • Clean energy and renewable energy advocacy
  • Environmental justice initiatives
  • Climate change mitigation and adaptation

Secondary Focus (20% of grants):

  • Wildlife and habitat conservation
  • Protection of endangered species
  • Land conservation and preservation

Tertiary Focus (10% of grants):

  • Women's reproductive health and rights
  • Population studies and family planning
  • Reproductive justice organizations

What They Don't Fund

While not explicitly stated, based on their giving patterns they do not fund:

  • Individual requests
  • Academic research institutions
  • Arts and culture organizations
  • General education programs
  • Healthcare (outside of reproductive health)
  • International organizations (primarily fund U.S.-based groups)

Governance and Leadership

Founder & President: Wren Winslow Wirth (established foundation in 1987) Trustees: Christopher Wirth, Kelsey Wirth (children of founders) Board Member: Teresa Heinz Kerry (philanthropist and environmental advocate) Executive Director: Morgan McMillan (compensation: $118,000 annually) Staff Size: 3 employees

The foundation is managed through Foundation Source, a comprehensive support services provider for private foundations, which handles administrative and compliance functions.

Application Process & Timeline

How to Apply

This funder does not have a public application process. The Winslow Foundation operates on an invitation-only basis and explicitly states they make "contributions only to preselected charitable organizations." They do not accept unsolicited grant applications, proposals, or letters of inquiry. Grants are awarded at the discretion of the board to organizations with whom they have established relationships.

Getting on Their Radar

Based on their giving patterns and board connections, organizations may come to their attention through:

  • Connections with other environmental funders in their network (they often co-fund with foundations like MacArthur, Hewlett, and Packard)
  • Leadership in high-impact environmental campaigns that gain national attention
  • Relationships with board member Teresa Heinz Kerry's philanthropic network
  • Participation in collaborative funding initiatives around climate action
  • The foundation appears to identify new grantees through peer foundations and trusted advisors in the environmental movement

Decision Timeline

Not publicly disclosed. As a private foundation making discretionary grants, timing likely varies based on board meeting schedules.

Success Rates

Not applicable - invitation-only funding model

Reapplication Policy

Organizations receiving grants often receive multi-year or recurring support, suggesting strong continuity with existing grantees.

Application Success Factors

Based on analysis of their grant recipients and patterns:

Characteristics of Funded Organizations:

  • Strong track records in environmental litigation or advocacy (e.g., League of Conservation Voters, Rainforest Action Network)
  • Organizations leading grassroots climate movements (e.g., Sunrise Movement Education Fund, Mothers Out Front)
  • Groups focused on environmental justice in communities of color
  • Organizations with national reach or significant regional impact in priority states
  • Groups that combine advocacy with direct action or community organizing

Common Grant Purposes:

  • General operating support for established environmental leaders
  • Specific campaigns targeting fossil fuel divestment or renewable energy adoption
  • Legal action to protect environmental regulations
  • Grassroots organizing and movement building
  • Youth climate activism and education

Notable Recent Grants:

  • $250,000 to Mothers Out Front for climate advocacy
  • Consistent multi-year support to National Parks Conservation Association
  • Regular funding to Planned Parenthood affiliates for reproductive health services
  • Support for environmental litigation through Government Accountability Project

Key Takeaways for Grant Writers

• The Winslow Foundation is exclusively invitation-only - do not send unsolicited proposals or inquiries • Focus on building visibility and relationships within the environmental funding community, particularly with foundations they co-fund with • The foundation values long-term partnerships, providing multi-year support to organizations demonstrating impact • They prefer funding established organizations with proven track records over startup nonprofits • Geographic presence in California, New York, Massachusetts, or Colorado may increase likelihood of consideration • The foundation maintains a low profile by choice - respect their privacy and do not attempt direct outreach • Best pathway to support is through excellence in environmental or reproductive health work that gains recognition from peer foundations

References

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