Organized and opened for business at its present location in 1886 by William J. McDonald (1844-1926), Civil War veteran and lawyer. Earlier he had opened the Citizens Bank of Clarksville and in 1889 he established a Delta County Bank. Under his shrewd leadership the banks prospered. Although careful in the granting of loans, he was also lenient about their repayment and seldom foreclosed. Aside from McDonald, the original stockholders included George F. Hicks, A. G. Hubbard, Edward Reuss, and R. F. Scott, Sr.
McDonald was bank president for many years and upon his death, left the bulk of his estate to the University of Texas to erect an observatory. In 1939 McDonald Observatory, in West Texas, was dedicated.
Present bank building was completed in 1916, but less than 3 months later was gutted by a ruinous city-wide fire. Within the year, however, it was restored.
Throughout the years, the bank has been a bulwark of the area's economy. During the Great Depression of the 1930s, its loans enabled many merchants and farmers to stay in business. In 1951 the bank portion of the building was remodeled. The present chairman of the board is Michel T. Halbouty and president is C. Glynn Lowe.