In What to Wear on Job Interview, suit or a bathrobe I wrote that you should wear a suit.

For some companies a suit may be overdressing. But it is a difficult call, especially for guys, you are in a suit or you are not in a suit. But it is better to do the error on the side of over-dressing than under-dressing.

Over-dressing with a suit in a place where it is not common to wear suit it can give the impression that you are out of touch with the companies’ culture and that you do not fit in, and have done a poor research to find out what is the company’s culture. If you feel that this company is very casual, it can be an option to ask beforehand, “The company where I worked before we dressed casual, is it OK to come dressed casual?”.

Anyway, research what is the dress code at the company and take it up one notch when you go for the job interview.