SOUTHBOROUGH — It’s official: Costco has signed its lease.
Purchased by Framingham-based Atlantic Management Corporation in January 2025 for $6.9 million, 21 Coslin Drive is a 17.81-acre lot in Southborough with an adjoining 7.3-acre lot in Westborough. The property is adjacent to Route 9, feet from Interstate 495, and soon to be home to Costco and its proposed 825 parking spaces.
In October, Southborough’s Town Meeting overwhelmingly (771-12) approved an amendment to the town’s zoning that allowed for Costco to be built on the site…