Mahlon Betts (1795–1867) was a carpenter, railroad car builder, shipwright, businessman, banker, and legislator who helped found three of Wilmington, Delaware's major manufacturing enterprises: the Harlan and Hollingsworth Company, the Pusey and Jones Company, and the Betts Machine Company.
Born in Attleboro in Bucks County, Pennsylvania, on March 16, 1795, Betts came to Wilmington in 1812. On November 8, 1818, he married Mary R. Seal at the Wilmington Friends Meeting. In 1828 (or 1829), he built a foundry at 8th and Orange Streets and there installed the state's first stationary steam engine.
On March 1, 1836, Betts joined Samuel N. Pusey to launch Betts & Pusey, which built railroad cars at a plant at Water and West Streets. He eventually leased the foundry to his son Edward (1825–1917), who carried on the business.
In 1837, Mahlon became a director of the Wilmington and Susquehanna Railroad. The railroad soon merged into the Philadelphia, Wilmington and Baltimore Railroad, which thenceforth operated the first rail link from Philadelphia to Baltimore. (This main line survives today as part of Amtrak's Northeast Corridor.) Betts became a director in the merged railroad, and his service as a railroad executive is noted on the 1839 Newkirk Viaduct Monument in Philadelphia.
He was also a director of the National Bank of Wilmington and Brandywine, the president of the Mechanics Bank, and the president of First National Bank of Wilmington.
In the 1840s, he served in the Delaware legislature, first as a representative and then as a senator.
Mahlon Betts died in Wilmington on March 4, 1867.