1234, Main Street
Boston, MA 02123
04 April, 2005
<Recipient Address Goes Here>
The unfortunate purpose of this letter is to complain about the rude treatment I received while patronizing <bank name>. While conducting business on <date>, <name of employee or description of the person’s position> <description>. While I am not usually one to complain, I found this behavior exceedingly unprofessional and knew that you would want to know about it so you could do something to rectify the problem.
I have been a customer at your bank since <year> and have always been satisfied with the service I have received there. I am hopeful that this incident was a “fluke” and that it won’t happen again.
Thank you for your time and consideration of this matter.
encl: <List of enclosed items goes here>