Greene County Bancorp

In 1998, The Greene County Savings Bank changed its name to The Bank of Greene County and went public, establishing a holding company – Greene County Bancorp, Inc. The bank also established a Charitable Foundation to support education, the arts, affordable housing, and other worthy causes. In 2016, including that year's grants, the Bank of Greene County Charitable Foundation surpassed $1 million in grants awarded since inception in 1998.

In 1999, the bank's common stock was approved for listing on NASDAQ under the symbol GCBC. The bank also purchased and renovated a historic art deco building at 302 Main Street, moving their administrative headquarters to the new building. Built in 1931 as the Cooperative Insurance Building, it was designed by architect E. P. Valkenburgh of Middletown. Over the next few years, new branches would be opened in Tannersville, Westerlo, Hudson, Catskill, Greenport, Chatham, Ravena, Germantown, Kingston, Copake, Woodstock, and Albany. The existing Coxsackie and Cairo branches were also moved and expanded.

J. Bruce Whittaker retired on June 30, 2007, after 20 years as president and CEO. He was succeeded by Donald Gibson, who started with the bank in 1987, and was promoted to senior vice president of commercial and retailing banking in 2003.In 2014, The Bank celebrated its 125th Anniversary by ringing the NASDAQ opening bell in Times Square.In late 2014, the Bank announced its first Ulster County Branch location in Kingston, NY, which opened in early 2015. The Bank opened its second Ulster County location, in Woodstock, in the fall of 2018, and its third location in Albany County, on Wolf Road in the Town of Colonie, in 2020.

On February 17, 2016, Greene County Bancorp, Inc. declared a 2-for-1 stock split on outstanding common stock. The stock split essentially gave shareholders of record 2 shares for every 1 share owned, and halved the stock price at the time of the split.In June 2016, GCBC stock was included in the FTSE Russell 3000 for the first time. In 2022, the GCBC stock was included in the Russell 2000 Index for the first time. Due to continued growth, the Bank moved its Customer Service Center to a stand-alone building in the Fall of 2021.On March 3rd, 2022, the Bank purchased the historic Tanners Building as a continuation of its investment in historic preservation.