I looked it up.
Common law is only recognized in Alabama, Colorado, District of Columbia, Iowa, Kansas, Montana, New Hampshire (for inheritance purposes only), Oklahoma, Pennsylvania, Rhode Island, South Carolina. Texas and Utah .
The web page says:
Contrary to popular belief, even if two people live together for a certain number of years, if they don't intend to be married and present themselves to others as a married couple, there is no common law marriage. More particularly, a common law marriage can occur only when:
a heterosexual couple lives together in a state that recognizes common law marriages
for a significant period of time (not defined in any state)
holding themselves out as a married couple -- typically this means using the same last name, referring to the other as "my husband" or "my wife" and filing a joint tax return,
intending to be married. "
It says that unless all four conditions are met, then there is no common law marriage. Interesting! Thanks for bringing this up - I had no idea I was this interested in this subject.