https://www.oneilattorneys.com/documents/ONeilAttorneysCommonLawMarriageTX_Web.pdf
“Many people think the following situations constitute or raise a question about a couple’s marital status under common law:
Myth 1: If we live together for 6 months or more, we are common law married.
Myth 2: If we move in together at all, we are common law married.
Myth 3: If we get engaged, we are agreeing to be common law married.
Myth 4: If my girlfriend tells someone that we are married but I don’t agree, then we might be common law married.
Myth 5: If my girlfriend uses my last name without my permission, then we might be common law married.
Myth 6: If we agree to get married in the future, we are common law married now.
Myth 7: If we agree to be married but never move in together, we still might be common law married.
Myth 8: If we talked about being married but never told anyone, we might be common law married.
Myth 9: If we have kids together and they have the father’s last name, we are common law married.
Myth 10: If we agree to be common law married, then we can agree to be divorced the same way.
As you will see, each of these situations is merely folklore and these are not examples of a common law marriage.”
“WHAT ARE THE RULES FOR COMMON LAW MARRIAGE IN TEXAS?
In order to meet the requirements of an informal/common-law marriage in Texas the man and woman must:
1. Agree to be married;
2. Live together as husband and wife, and
3. Represent to others in Texas that they are husband and wife,
which is often referred to as “holding out” to others that you are husband and wife.
All three elements must exist at the same moment in time to establish a common-law marriage.
In addition to meeting the above requirements, you must also prove that both husband and wife have the capacity to enter into the marriage. In the state of Texas, to have the capacity to enter into a common-law marriage, you must be members of the opposite sex, you must both be at least 18 years of age or older, you cannot be related, and you must not be currently married to someone else. If you can fulfill these requirement.”