PricewaterhouseCoopers has signed a 15-year lease to occupy the majority of a planned office tower in Boston’s Seaport District.

Inking a deal with the accounting firm gave Skanska USA Commercial Development the anchor tenant it needed to begin construction on the 440,000-square-foot tower at the southeast corner of Seaport Boulevard and Boston Wharf Road.

"We are proud to partner with PwC in delivering Seaport Square’s first major office building which will complement Boston’s growing Innovation District as it continues to attract pioneering businesses," Shawn Hurley, executive vice president of Skanska in Boston, said in a statement.

PwC will occupy 330,000 square feet of the 17-story building on land in Seaport Square, currently known as Parcel 1. The accountants will occupy the space beginning in October 2015, according to information released by Skanska. 

The building will include 20,000 square feet of ground floor retail being handled by WS Development.

"We will have a vibrant mix of amenities and dining that will serve employees, visitors and residents of the area," Dick Marks, partner at WS Development, said in the statement. "The interest from local and national retailers in the Seaport District has been quite incredible and continues to grow given the recent announcements about the area."

William Anderson and David Martel of Cushman Wakefield represented Skanska USA Commercial Development and Timothy Dempsey, Ogden White III and Amy DeAngelis of CBRE represented PwC.

Skanska is also working to build the nearby Watermark Seaport with Twining Properties, a 346-unit apartment building with ground-floor retail that will be immediately adjacent to Skanska’s new office tower. Both projects are part of the 6.35 million square feet of residential, commercial, hotel, retail and cultural space planned for Seaport Square.