BOSTON-Accounting giant Pricewaterhousecoopers will make a new tower being developed by Skanska USA its Boston headquarters starting in the fourth quarter of 2015. Currently based in 376,000 square feet at 125 High St., PwC will occupy 75%, or about 330,000 square feet, of the 440,000-square-foot office building in Boston’s Seaport District.

Skanska is investing $265 million to build the office tower at the southeast corner of Seaport Boulevard and Boston Wharf Road. This past December, the company acquired Parcel L1 of Seaport Square in Boston’s Seaport District from MS Boston Seaport LLC, a partnership between Morgan Stanley and Boston Global Investors, for $33 million.

William Anderson and David Martel of Cushman & Wakefield represented Skanska USA Commercial Development in lease negotiations, while CBRE‘s Timothy Dempsey, Ogden White III and Amy DeAngelis represented PwC, which is looking to increase its local headcount to about 3,000. Skanska USA Building will be handling the construction of the new tower, which is aiming for LEED Gold certification or better, and includes 20,000 square feet of ground floor retail being handled by WS Development.

In partnership with Twining Properties, Skanska is also developing Watermark Seaport, an apartment building with 346 residences and ground-floor retail, immediately adjacent to the new office tower. Both projects are part of MS Boston Seaport’s long planned Seaport Square development, which will contain 6.35 million square feet of residential, commercial, hotel, retail and civic/cultural space in a 20-block cluster.