One of the primary differences is the way banks ( like chase, amex centurion bank, BofA etc) and credit unions charge fees and what they do with the profits they make. Banks are out for profit strictly speaking. They do not offer a service to a community unless its profitable to them. They are stereotypically greedy and self centered. Credit Unions are setup to benefit members of a community or profession (usually people with similair backgrounds, interests, occupations etc.) and are non profit meaning whatever profit they make is passed back to the members in the form of higher interest rates on deposits and lower interest rates on loans/credit cards etc. Credit Unions have many of the same expenses as banks like paying for the buildings, insurance and employee salaries but the rest is pretty much divided up and passed back to the members to try and help one another. Also credit unions are mostly local, there are national credit unions but for the most part they are local, statewide or regional most of the time.
Being smaller and concentrating on serving and helping a smaller, more specific group of people allows them to be more competitive most of the time.
