The Security Bank and Trust Company traces its history to the Wharton National Bank. The second banking institution to open in the city, the Wharton National Bank was organized in 1902, and closed in 1915. Following reorganization, the bank reopened in January 1916 as Security Bank and Trust Company. A State of Texas charter was granted in May 1918.
The first officers of the Security Bank and Trust Company were A. A. Mullins, R. J. Wright, Tom Brooks, and E. Hawes, Sr. The institution's board of directors counted among its member's civic leaders and prominent businessmen of the community, including G. A. Harrison, T. Gordon, and G. H. Northington, Sr.
The Security Bank and Trust Company has been an important part of Wharton's history since its opening, and has contributed to the community in many ways. Its directors were instrumental in the organization of major civic activities, including the Wharton County Youth Fair, and the bank was a catalyst in the founding of Wharton County Junior College.
Security Bank and Trust continues to serve Wharton and the surrounding communities, actively maintaining an involvement in civic projects.