A rare undeveloped lot along Boston's famed Newbury Street shopping corridor will soon be turned into an office and retail building.

L3 Capital secured a $56M construction loan and plans to break ground speculatively this month on a 43,500 SF mixed-use development at 149 Newbury St., JLL announced Monday.

JLL's Jonathan Schneider and Michael Morretta represented the Chicago-based developer in securing a three-year loan from Bank of New England and Needham Bank. JLL's Patrick Nugent and Bryan Sparkes are managing the project's office leasing efforts.

The five-story project is expected to deliver in Q2 2023, JLL said. It will consist of 27,500 SF of office and 16K SF of retail. L3 is working with Nelson Worldwide on the project's design.

“The combination of topflight ownership, exceptional location and the draw of new state-of-the-art construction will undoubtedly make this project a huge success,” Schneider said in a release.

The property has previously been used as a parking lot. It sits at the intersection of Newbury and Dartmouth streets in the Back Bay neighborhood, one block from the Copley MBTA stop.

Newbury Street, which for decades has been Boston's go-to destination for high-end shopping, has lost some ground in recent years as new retail hubs have emerged in other parts of Back Bay, plus the Seaport and Fenway areas. The pandemic further disrupted the retail corridor, but those headwinds haven't stopped new stores from opening on Newbury Street over the last two years.