Mass General Brigham Inc. secured a bond package to help cover the costs of its ongoing expansion at its West End campus.

MassDevelopment announced Thursday that it has issued $865.5M in tax-exempt bonds on behalf of the hospital system for its 482-bed Ragon Building, a health care facility under construction at 55 Fruit St.

J.P. Morgan Securities LLC acted as the lead underwriter and sold the bonds through a public offering.

“MassDevelopment is pleased to issue tax-exempt bond financing to help the organization expand this legacy and look to the future with key campus investments across Boston,” MassDevelopment President and CEO Navjeet Bal said in a statement.

The Fruit Street project centers on expanding the hospital system's oncology and cardiovascular services. The new facility is expected to be completed in two phases, the first by 2027 and the second by 2030.

Not all of the bonds' proceeds will be earmarked for that project alone, however.

Funding will also be put toward the continued redevelopment of the hospital system's Brigham and Women's Faulkner Hospital campus at 1153 Centre St. in Jamaica Plain.

The bond financing will help offset the cost of work done to add five stories to the Centre Street hospital, the purchase of new equipment, and some additional upgrades and renovations.

Proceeds will also help the hospital system refinance its existing debt.

Mass General Brigham first unveiled plans for expansion in 2019 and estimated two years later that it would cost some $2B.

The hospital system reported a $59.2M operating gain last year, up from a $45.7M gain the year prior, The Boston Globe reported. In February 2025, the hospital undertook the largest layoff in its history, cutting roughly $240M in salary and benefits.

MassDevelopment has helped other healthcare institutions seeking to expand in the city. In 2023, Boston Medical Center secured $232M in sustainability bonds for renovation and expansion to its South End campus. The expansion included 70 inpatient beds, including 10 intensive care unit beds and 60 surgical beds.