Traders, brokers, auctioneers, and consigners all benefited from the buying and selling of enslaved men, women, and children, yet profits generated through the trade were not limited to those with direct ties to slave sales. Banks were heavily invested in the trade at both the local and and national levels. Slave traders across the country relied on bank loans for the initial outlay of funds needed to assemble slave coffles, and planters frequently financed purchases through bank-supported mortgages. In 1831–32 alone, loans extended to Franklin, Armfield, and Ballard's slaving firm constituted 5 percent of the total commercial credit on offer from the Second Bank of the United States.

Other industries benefited too. Insurers underwrote policies covering slave shipments by rail, river, land, and sea. Food purveyors supplied salt pork, corn, beans, and other provisions to coffle drivers and slave-pen owners. Notaries, lawyers, and other bureaucrats collected fees for each piece of paper generated by slave transfers and sales. During the early stages of ready-to-wear clothing manufacture, companies such as Brooks Brothers and S. Hopkins Jr. supplied "plantation clothing" to planters and cheaply made suits, top hats, head wraps, and dresses to auction houses eager to spruce up their human wares. Steamboat companies and ship's captains, too, saw their purses swell with funds paid to transport slave cargo. And medical providers—including doctors, hospitals, and private clinics—profited by bringing individuals sickened by their long journeys south back to full strength so that their owners might fetch high prices at their sale.