Trimix Foundation

The Trimix Foundation, established in 1997 by David and Gail Mixer, operates as a family foundation managed through Pathstone Family Office in Providence, Rhode Island. The foundation's core mission centers on improving and expanding quality housing for low-income communities and reversing urban blight in Berkshire County, Massachusetts, but its grantmaking extends to youth development, education, animal welfare, and limited arts support. The foundation employs a relationship-based grantmaking approach, accepting Letters of Inquiry via traditional mail rather than maintaining an online portal. With $45 million in assets and over $60 million distributed since inception, the foundation has scaled back from 33 grants per year (2019) to just 3 grants (2024), signaling a strategic shift toward fewer, larger investments. The Mixer family maintains operational control through a six-member all-family board (Mark, David, Brian, and Michael Mixer, plus Arthur Duffy as treasurer and Matthew Thibault as secretary), with Mark Mixer currently serving as president. The foundation's connection to the Mill Town Foundation—which received $592,471 in 2024 and where David Mixer serves as Vice President—suggests a strategic channeling of philanthropic efforts through an affiliated intermediary focused on Berkshire County revitalization.

The Trimix Foundation has undergone a dramatic shift in grantmaking patterns over the past five years. Annual awards declined from 33 grants in 2019 to just 3 grants in 2024, while average grant size has increased substantially. In 2024, the foundation distributed $1.097 million across only three recipients: Mill Town Private Foundation ($592,471), Union College in Schenectady ($500,000 in two grants), and Railroad Street Youth Project ($5,000). This concentration contrasts sharply with the 2019 pattern of $2 million spread across 33 organizations with typical grants of $25,000–$100,000. Total assets have grown from $29.6 million (2018) to $45.2 million (2024), reflecting strong investment performance. Annual giving has fluctuated between $874,000 and $2.5 million, with the recent trend showing lower total disbursements but higher per-grant amounts. The foundation holds virtually zero liabilities ($1,810 in 2019) and maintains a conservative financial posture. Board members serve without compensation, keeping administrative costs low. The types of support offered include general operating funds, project support, endowment funding, capital building funds, and challenge grants.

The Trimix Foundation is notably smaller than the dominant community foundations in its two-state footprint (Rhode Island and western Massachusetts). Its recent pivot to concentrating grants through Mill Town Foundation distinguishes it from peers that typically fund dozens of organizations annually. The foundation's $45M asset base positions it as a mid-size private foundation, but its declining grant count (33 in 2019 to 3 in 2024) makes it increasingly selective compared to similarly sized funders. Its giving rate of approximately 2.4% of assets in 2024 falls below the IRS-required 5% minimum distribution, though qualifying distributions may include other exempt-purpose expenditures.

The Trimix Foundation's most recent filing (2024) shows total assets of $45.2 million with $1.097 million in grants distributed to just three recipients. The single largest grant of $592,471 went to Mill Town Private Foundation, an affiliated entity where founder David Mixer serves as Vice President. Mill Town Foundation focuses on Berkshire County revitalization, suggesting Trimix is increasingly channeling its housing and community development mission through this intermediary. Union College in Schenectady, NY received $500,000 across two separate grants, reflecting the Mixer family's educational giving interests. Railroad Street Youth Project in Great Barrington, MA received $5,000—a longtime grantee aligned with the foundation's Berkshire County focus. The dramatic reduction in grantee count (from 33 in 2019 to 3 in 2024) represents either a strategic consolidation or a winding down of broader grantmaking in favor of the Mill Town Foundation channel. The foundation continues to be managed through Pathstone Family Office (formerly Rex Capital Advisors) in Providence, RI, with Mark Mixer serving as president and all six board members being family members or close associates.

Despite the Trimix Foundation's declining grant count, organizations can position themselves for funding through these approaches: (1) Submit a Letter of Inquiry via traditional mail to Mark Mixer at Pathstone Family Office, 50 Park Row West Suite 113, Providence, RI 02903. Include organizational letterhead, a description of the organization, the purpose and amount of the funding request, and an IRS 501(c)(3) determination letter. (2) Call (401) 383-5370 before submitting to introduce your organization and confirm current funding priorities, as the foundation's interests may have narrowed significantly given recent grantmaking patterns. (3) Organizations in Berkshire County, MA will have the strongest alignment—the foundation's core mission targets housing and community revitalization in that specific region. (4) Consider whether applying directly to the Mill Town Foundation may be more productive, as Trimix appears to be channeling an increasing share of its philanthropy through that affiliate. (5) Demonstrate direct service delivery and tangible community impact rather than research or advocacy; past grantees like Boys and Girls Clubs, Amos House, and Railroad Street Youth Project all emphasize hands-on programming. (6) The foundation supports multiple types of funding including general operating, project support, endowment, capital building, and challenge grants—tailor your ask to the type that best fits your need.