The National Association of Counties and National League of Cities are about to become roommates, with the groups announcing Monday they will share a single headquarters starting July 2016.

The two associations will occupy three floors in an eight-story office building at 660 North Capitol St. NW in Washington, D.C., roughly one block west of Union Station. Both groups participated in the design of the new offices.

NACo and NLC said in a joint statement the move would allow them to share resources and better coordinate efforts between their members. NACo will take up 39,987 square feet of space in the new offices while NLC will occupy 33,654 square feet. The two organizations will share a 4,730-square-foot conference center.

The groups didn't say whether to co-location would mean a change in staff size for either organization. The $15 million-revenue NACo reported 99 staff in 2014, while the $15 million-revenue NLC reported 114 staff, according to their most recent tax records.

"This first-of-its-kind collocation allows our members to work more closely with NACo and our partners in Congress to magnify issues that matter most to local officials," NLC CEO Clarence Anthony said. "Our new headquarters is designed to be a hub of city-based innovation and engagement, as well as a ‘city hall in Washington' for our members."

"This new space will be the center of local leadership and innovation on Capitol Hill," NACo Executive Director Matthew Chase said. "With our partners at the state and federal levels, we look forward to working more closely with NLC to confront some of the greatest challenges our communities face."

NACO is currently located at 25 Massachusetts Ave. NW. NLC headquarters is at 1301 Pennsylvania Ave. NW.

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