The Calvert County Purchasing Office is responsible for procuring commodities and services required by Calvert County Government. The Department of Public Works, the Capital Projects Coordinator and the Purchasing Office administer the procurement of professional services and major construction for capital projects.Calvert County Government uses eMaryland Marketplace, the State of Maryland bidding website, to bring you more efficient and effective bidding and procurement opportunities. The Purchasing Office is located in the County Services Plaza, 150 Main Street, Suite 105, Prince Frederick, Maryland 20678. Please contact 410-535-1600, ext. 2288. eMaryland Marketplace