Amegy Bank, originally established as Northwest Crossing National Bank on October 18, 1982, underwent several changes throughout its history. In 1990, the bank changed its name to Southwest Bank of Texas National Association and relocated its main office to 4295 San Felipe in Houston, Texas. The bank continued to evolve, moving its headquarters again in 1996 to 4400 Post Oak Parkway in Houston. Over the years, Amegy Bank expanded through a series of acquisitions, including notable banks such as Pinemont Bank in Houston in 1997 and Fort Bend Federal Savings and Loan Association in Rosenberg, Texas, in 1999. The institution changed its name to Amegy Bank National Association on March 7, 2005, and continued its growth with additional acquisitions, including Klein Bank in Spring, Texas, and Lone Star Bank in Dallas, Texas, in 2004. In December 2015, Amegy Bank merged with Zions First National Bank and subsequently changed its name to ZB, National Association on January 1, 2016. Finally, on September 30, 2018, the institution was renamed Zions Bancorporation, N.A.

Below is a list of some important events in bank's history, including mergers and acquisitions.

09-30-2018Changed Institution Name to Zions Bancorporation, N.a..

01-01-2016Changed Institution Name to Zb, National Association.

12-31-2015Merged and became part of Zions First National Bank (2270) in Salt Lake City, UT.

09-05-2007Acquired Intercontinental National Bank in San Antonio, TX.

03-07-2005Changed Institution Name to Amegy Bank National Association.