Savings Institute Bank & Trust

/Home/1. Search Connecticut Banks/Banks - Windham County, CT/Banks - Willimantic, CT

Savings Institute Bank & Trust
803 Main Street
Willimantic CT, 06226

Phone: 860-423-4581

Lobby Hours
Mon - Wed: 9:00 - 4:00
Thur, Fri: 9:00 - 6:00

Driveup Hours
Mon - Wed: 8:30 - 5:00
Thur, Fri: 8:30 - 6:00


The Savings Institute was incorporated by an act of the Connecticut legislature in 1842 under the name Willimantic Savings Institute. It was shortened to Savings Institute in 1991 to reflect the Bank’s expanded geographic territory and its dedication to further expansion. In 1999 the Savings Institute Board of Directors voted to establish SI Bancorp, a mutual holding company, which positioned the bank to seize new markets as they emerged and to compete in the financial services marketplace.

The Willimantic Savings Institute opened its second office in Hebron in May of 1974. This marked the initial step in the Bank’s expansion plan to become eastern Connecticut’s premier community bank. Other branches were opened in Lebanon (December 1978), Franklin (January 1983-August 2001), and Stonington (May 1987). In October 1990, The Willimantic Savings Institute acquired Brooklyn Savings Bank which gave the Bank a presence in Brooklyn, Canterbury, Danielson and Moosup. In May 1991, the Mansfield Office and Financial Center were opened and, in August of 1991, Enfield National Bank was acquired.

The next period of retail office development began in 1996 with a $1 million renovation project at the Bank’s Corporate Headquarters/Main Office in Willimantic, and it continues today: Dayville, September 1996; Groton, October 1997; Norwich, January 1998; and West Main Street in Willimantic, April 1998. The growth continued as the Bank moved into the new millennium: North Windham, March 2000; Lisbon, August 2001; Tolland, June 2005; South Windsor, October 2005; East Lyme, March 2006; Gales Ferry, August 2006; and East Hampton, August 2007. In January of 2008, the Bank acquired the Colchester branch office of Eastern Federal Bank and in March of the same year acquired the New London branch office of Bank of Southern Connecticut, giving the Bank a presence throughout eastern Connecticut.

In 2000, the Bank converted to stock form and became the wholly-owned subsidiary of SI Bancorp, Inc., a Connecticut –chartered mutual holding company. On August 6, 2004, Savings Institute converted to a federal charter and now operates under the name Savings Institute Bank & Trust Company. At that time, SI Bancorp, Inc. converted to a federal charter operating under the name SI Bancorp, MHC and transferred all of the common stock of the Bank to SI Financial Group, Inc.

To continue our long-standing commitment to our local communities, a charitable foundation, the SI Financial Group Foundation, has been established as part of the Bank’s conversion. This new Foundation succeeds the Savings Institute Foundation which was established in 1999 and will continue to assist non-profits in the area with funds that will enable them to help the hungry, shelter the needy, and assist kids with educational opportunities that might not otherwise be possible.

Through changing economic times, bank deregulation, and new branch development and consolidation, the Savings Institute Bank & Trust has remained true to its original charter and mission statement: “to exist to experience the joy of enriching the lives of individuals and businesses within our communities.”

© 2009 The Savings Institute Bank & Trust,
All Rights Reserved