The two-story reception and pre-function area at Jones Day’s new offices in the South Station Tower/Image courtesy of Elkus Manfredi Architects

The first office tenant to lease space in the new South Station Tower selected Boston-based Elkus Manfredi Architects to design its 41,000-square-foot workspace.

Law firm Jones Day will occupy the 22nd and 23rd floors of the 51-story office and condominium tower scheduled for completion in March 2026.

The legal industry has the largest increase in office space requirements in Boston this year, according to a report from brokerage Avison Young. Leasing activity rose 332 percent from the previous year, including Ropes & Gray’s renewal of its 413,000-square-foot Prudential Tower offices.

Currently, 13 firms are scouting potential office leases in the over-20,000 square foot range, Avison Young reported.

“Law firms that will succeed in the future must be based in agile, flexible and resilient workplaces that can change without fuss, strengthen the culture that defines their practice, and carry the firm’s vision through the coming decades,” Elkus Manfredi Principal Elizabeth Lowrey said in a statement.

Developer Hines began construction of the long-anticipated air rights project in 2021 after receiving $870 million in construction financing. A second office tenant, insurer FM Global, leased 57,000 square feet in January.

The Collaborative Companies of Boston is marketing the residential segment on the upper floors of the spire, comprising 166 luxury condominiums in the Ritz-Carlton Residences.