Technically, no. There are only forty-six states in the United States - Kentucky, Massachusetts, Pennsylvania, and Virginia are commonwealths.

Before you even begin to discuss the concepts and differences between these designations, you have to first determine where you are located. So, where are you talking about? Commonwealths and States, in domestic law, are pretty much treated the same. So much so that one could say there is no practical difference. As a basic rule, in the United States of America, commonwealths and states are treated the same under the U. S. Constitution.

Like the other comments following, it depends on what kind of commonwealth you're talking about; some consider Puerto Rico a commonwealth (which has some benefits of federal assistance, but restricted voting rights, etc).

However, if you're asking about Virginia, Kentucky, Massachusetts, or Pennsylvania (the four "states" in the US that call themselves a commonwealth), in a commonwealth landowners do not possess mineral or oil rights to their land. They don't actually own their land but own its use. However this does not significantly differentiate their structure or self-government in any way from other states in the Union.

Studying the constitutions of most states you will find similar wording regarding the states identity or "sovereignty." To the federal government all states are created equal. The differences come about through actions of the states (or in VA, MA, PA and KY the commonwealth). Relative to the US there is NO difference between a state and a commonwealth although there are certainly differences in how each state is governed.