JLL Closes $856M Financing for Winthrop Center, Including Record $281M C-PACE Loan from Nuveen Green Capital

JLL's Capital Markets group has closed $856 million in financing for Winthrop Center, the 691-foot mixed-use tower developed by Millennium Partners in downtown Boston, the firm announced Aug. 26. The capitalization pairs a $281 million Commercial Property Assessed Clean Energy loan for the residential component with a $575 million securitized loan for the office portion, drawing institutional capital from Nuveen Green Capital, Morgan Stanley, and Barclays.

Deal Structure: Two-Part Capital Stack

JLL arranged the financing on behalf of Millennium Partners, structuring the transaction in two distinct tranches to address the project's mixed-use composition. The $281 million C-PACE loan, provided by Nuveen Green Capital, carries a 20-year term and is secured by the residential inventory at The Millennium Residences at Winthrop Center, which comprises 317 luxury condominium units across approximately 510,000 square feet. Nuveen Green Capital described the transaction as the largest C-PACE-financed deal in New England.

The second tranche — a five-year, $575 million securitized loan — covers The Offices at Winthrop Center, an approximately 823,856-square-foot Class A office building certified as the world's largest Passive House office building. Morgan Stanley and Barclays provided that financing. The combined $856 million in debt sits against a stated development cost of approximately $1.3 billion for the overall project.

The JLL Debt Advisory team representing the borrower was led by Executive Managing Director Riaz Cassum, Managing Director Andrew Gray, Vice President Robyn King, and Analyst David Mega.

Property Overview: Winthrop Center

Winthrop Center, located at 115 Federal Street and 250 Devonshire Street in Boston's Financial District, stands as the tallest building in Boston's downtown core at 691 feet. The project was developed by Millennium Partners, a luxury mixed-use developer founded in 1991 with a portfolio that includes Millennium Tower and Millennium Place, also in Boston.

The office component spans approximately 823,856 square feet of Class A space and carries Passive House Institute certification, a designation that emphasizes energy efficiency and indoor environmental quality. The residential component, branded as The Millennium Residences at Winthrop Center, offers 317 units across roughly 510,000 square feet, marketed as ultra-luxury condominiums with views of the Boston skyline, Charles River, and Boston Harbor.

The building is positioned in close proximity to South Station and approximately 28 million square feet of Class A office inventory in the surrounding downtown submarket.

Sponsor and Lender Commentary

"This financing is a key milestone that reflects the confidence that leading institutional partners continue to place in Winthrop Center," said Christopher Jeffries, Founder of Millennium Partners. "Winthrop Center was conceived as a landmark building for Boston with significance well beyond the city, setting a global standard for sustainable mixed-use development. We are proud to see that vision recognized from our financial partners."

"This transaction reflects the convergence of exceptional sponsorship, irreplaceable product and structural market dynamics that institutional lenders seek in today's environment," said Riaz Cassum of JLL. "Millennium Partners has an unmatched track record in Boston's luxury residential market. Winthrop Center represents the most evolved living and work experience the sponsor has ever created, combining world-class sustainability, five-star services, and extraordinary amenities for both residents and commercial occupants. This sizeable commitment from institutional lenders is a testimony to proven sponsorship, the asset's quality and the fundamental strength of both Boston's ultra-luxury condominium and trophy office markets."

"It was a pleasure to partner with JLL and Millennium Partners to capitalize this landmark project, which marks the largest C-PACE-financed transaction in New England," said Michael Doty, Senior Director of Originations for Nuveen Green Capital. "Through C-PACE's cost-effective financing, the sponsor was able to recapitalize the residences portion of the property alongside $575 million in financing from Morgan Stanley and Barclays for the offices, delivering an innovative capital structure that adds long-term value, while helping to ensure the success of The Millennium Residences and The Offices at Winthrop Center."

Market Context

The financing comes as Boston's downtown office market continues to navigate elevated vacancy and flight-to-quality dynamics, with institutional lenders showing selectivity toward assets with strong sustainability credentials and sponsor track records. The 20-year term on the C-PACE residential loan provides long-duration capital tied to the building's green design features, while the five-year structure on the office loan reflects a shorter-term approach in the current securitized lending environment.

The split structure allows different capital sources to address the distinct risk profiles of the condo inventory and the office cash flows within the same mixed-use tower. Nuveen Green Capital, an affiliate of Nuveen — the asset management subsidiary of TIAA — has originated more than $6 billion in sustainable commercial real estate financing and was involved in designing the nation's first statewide C-PACE program.

JLL's Capital Markets group operates with more than 3,000 specialists across offices in nearly 50 countries and provides debt advisory, investment sales, equity placement, and related services to real estate investors and occupiers globally.

Sources

JLL press release via PR Newswire, Aug. 26, 2026