"Principal" vs "owner"

What is the business perception of identifying yourself as the Principal vs the Owner? I assume they are largely synonymous (please tell me if there are subtle differences, but in a small business sense, they seem interchangeable). Using "Principal" to me has always sounded fancier :)

Also, as a small issue: Is "Principal" the correct spelling? It's not "Principle" is it? My spelling skills are terrible!

"Principal" has a specific meaning in the context of commercial law. From Wikipedia:

a principal is a person legal or natural–who authorizes an agent to act to create one or more legal relationships with a third party

Effectively, this means that the principal is the business. In the case of a corporation, say General Electric, the principal is General Electric itself, while Jack Welch was one of its agents during the 80s and 90s. In the case of a sole-proprietorship, the business and its owner are effectively one-and-the-same, so a person might realistically be called the principal in that situation, but pretty much no other.

I think I can shed some light on this subject. I will use an industry I am familiar with to illustrate. Many law firms these days are considered "small businesses." I live in a county with about 1.3 million residents, and some of the attorneys I am friends with refer to themselves as one of the following:

"Founder" "Owner" (less common) "Principal" "Partner" "Founding Partner"

As far as the most popular designation, it's tough to say. Partners tend to use "Partner" or "Founding Partner," while attorneys who are founders of a non-partnership structured firm, such as a professional corporations or professional limited liability company, tend to use, "Principal" or, "Principal Attorney." A good number of solo practitioners also simply use (Esq.), but some attorneys do not think this is in good taste (I have no idea why not).

I myself am a founder/owner of a Virginia criminal defense firm registered as a Professional Limited Liability Company (PLLC). I don't go around telling people I'm "Principal so and so," with the exception being my email signature. It is: FIRST NAME, MIDDLE INITIAL, LAST NAME, Principal Attorney. Quite frequently, people who call my firm do ask if they are talking to a firm leader (or something similar). This is the only reason why I see any benefit using "Principal." It makes people more comfortable and likely to trust they are contacting a decision maker.

Whoever thinks using the term "principal" is suggestive of a small business needs to get out more. I know two guys my age, 50. Each owns his own business and applies the term "principal" in regard to his respective position. The first privately owns a company that does about 13 million a year in gross revenue. Margins, including G&A, are in the 30-40% range. He sold his business for 35 million. The other "principal" markets 11 products as a manufacturers rep. He works with his son. His annual pay is around $450,000 while his son collects around $100,000. Hey, you can call me principal anytime.