First Niagara Bank Online Banking First Niagara Is now Operated by Key bank. First Niagara Bank was founded in 1870 as Farmers and Mechanics Saving Bank. It is a subsidiary of First Niagara Financial Group. It is headquartered in Buffalo, New York and has over 390 branches including in Pennsylvania, Massachusetts, and Connecticut. Customer Service Telephone 1(800)421-0004 Online Banking Login How to Log In: 1. Go to www.firstniagara.com. 2. On the log in area at the upper left side of…