Union County, Ohio Business Directory & Community Resources

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View the 2025 U.S. Census demographic profile for Union County

Union County — County Seat: Marysville

2026 Population Estimate: 74,909  |  Official Website: https://unioncountyohio.gov/

Union County is one of Ohio's fastest-growing counties, representing extraordinary growth from about 40,000 in 2000 — driven by the presence of Honda of America Manufacturing and suburban Columbus expansion. The county seat is Marysville, which is home to Honda's flagship North American assembly plant — the first Japanese automobile transplant factory built in the United States (opened 1982) — and remains one of the most significant manufacturing facilities in American automotive history, producing Honda Accord and Civic models. The massive Honda presence has created a dense ecosystem of supplier plants and has made Marysville and Union County among the most economically dynamic small counties in the nation. The county is also experiencing explosive residential growth as Columbus suburbs expand westward. Major employers beyond Honda include Scotts Miracle-Gro (headquartered in Marysville), Memorial Health, and dozens of automotive supplier companies. The Union County Covered Bridge festival celebrates local heritage.

▸ Key Industries & Major Employers
Automotive manufacturing, healthcare, and residential development (Columbus exurbs).
Honda of America Manufacturing (Marysville Auto Plant and East Liberty Auto Plant) is the county's defining employer, employing 10,000+ and driving an extensive supplier network. Other major employers include Memorial Hospital of Union County and Scott's Miracle-Gro (headquarters in Marysville).

▸ Notable Economic Development Initiatives
Honda's continued investment in Marysville—including electrification upgrades to produce EV-ready platforms—is the county's primary economic driver. The Union County Economic Development office supports Honda supplier attraction. Scotts Miracle-Gro's global headquarters drives additional business services and retail. Population growth from Columbus commuters is spurring significant residential and retail development.

▸ Infrastructure & Investment Highlights
US-33 and SR-4 provide primary highway access. The Honda Ohio plants are served by dedicated rail spurs. Water and sewer capacity in Marysville is being expanded to support residential and commercial growth. I-270 (Columbus outerbelt) is accessible 20 minutes south.