I worked in the home office and in the field. In the home office, the dress code is business professional. Men have to wear a dress shirt and a tie -- no exceptions, save for Casual Friday (which was usually in the summer months only).
The field is different. The 10,000 offices vary depending on the branch policy and the financal advisor's personal style, so I've seen everything from business professional to very casual.
Personally, given how conservative the financial industry is in terms of dress I would advise wearing business professional to business casual (no tie and a sportcoat) in the office. To me, it's a little disrespectful to clients not to be dressed a certain way because of the general expectation of what financial advisors do,