He had the highest net worth, US$350,000 (equivalent to $11,868,889 in 2023), of the 34 active resident slave traders indexed as such in the 1860 New Orleans census, ahead of Jonathan M. Wilson and Bernard Kendig.

[4] Poindexter is listed as the "shipper" of slaves from Charleston, South Carolina, on the ship John David Mongin bound for Savannah, Georgia, in 1829.

[11] According to an advertisement placed in the New Orleans Crescent in 1865, Poindexter's 4,000-acre (1,600 ha; 6.3 sq mi) Tensas Parish plantation was located about 3 miles (4.8 km) inland from St. Joseph on the Mississippi River, in an area said to be "the best cotton-producing country in the United States, between Natchez and Vicksburg, and nearly opposite Rodney."

[2] According to an analysis of historian Richard Tansey, Poindexter was the richest of the 34 men listed in the 1860 census of New Orleans as being slave traders.

[18] In November 1861, New Orleans auctioneer Norbert Vignié listed for sale "at 10+1⁄2 o'clock A.M. at the late residence of the deceased at the corner of St. Charles, or Nayades, and St. Andrew streets...7 bbl.

[19] In January 1862, Vignié advertised that he would sell "at the Merchants' and Auctioneers' Exchange, Royal street, slaves and property belonging to the succession of Thos.

According to research by historian Judith Schafer, after Poindexter's slaves were freed by the Emancipation Proclamation "many of them left his plantation, carrying off most of its movable property.

A few months later, Confederate cavalry burned all of the cotton stored on the property, to keep it out of enemy hands, and confiscated the plantation's corn to feed their horses".

[26] Similarly, in 1851, a Supreme Court of Alabama decision about the correct endorsement of a "bill of exchange" involved both Thomas B. and John J.

[29][30][31] The University of Virginia Libraries holds a letter to turfman William Ransom Johnson dated January 18, 1852 "from Thomas B. Poindexter, Louisville, Kentucky, which discusses a racehorse, 'Sally Morgan.'