Willis Tower Gets Another Year To Pay Off $1.3 Billion Loan: The largest commercial mortgage-backed securities loan scheduled to mature this year was a $1.33 billion mortgage on Chicago’s Willis Tower. The loan was to be paid off in full this month, but the borrowing entity affiliated with Blackstone Group exercised an extension option for another year to March 9, 2023. The 3.9 million-square-foot landmark owned has been combating weak demand in the West Loop office market. In the past 12 months, the building has posted negative net absorption, the difference between move-ins and move-outs, of 328,000 square feet, while the market has recorded negative 1.1 million square feet. United Airlines terminated three floors of its headquarters lease in the building in December and moved 900 employees to the suburbs.