A Boutique Investment bank is a small investment bank with anywhere from 2 to 40 professionals. Boutiques do the same work as the larger Bulge Bracket but usually work on smaller deals under $500 million.
The interview process at the boutiques is typically less structured than the bulge bracket process meaning there can be open-ended hiring dates opposed to bulge bracket which has recruiting deadlines. Also, the work environment at smaller banks is usually less stringent but this is not always true.
In certain cases it is actually harder to get a job at some of the most prestigious boutiques than it is at the large Bulge Bracket Investment Banks. Top boutiques that would fit this category include: Greenhill & Company, Evercore Partners, Lazard, Perella Weinberg Partners, and Houlihan Lokey.
At the top boutique and middle-market investment banks, your salary will be the same to the bulge bracket, but at the small boutiques the pay is usually discounted.
If you are finding yourself behind the bulge bracket recruiting schedule starting your recruiting search with the boutique investment banks would be my advice.
Here are great resources for breaking-down Boutique Investment Banks: