Both common law marriages and putative marriages are not real marriages. In other words, these marriages may be more challenging to prove in a court, than a real or traditional marriage.
However, there are many differences between common law marriages and putative marriages. A putative marriage is one in which a person believes himself or herself to be legally married, and may continue with this belief for years, even though the marriage was not valid. For example, say, a person is married to a person who is technically already married to someone else. This person may be said to be in a putative marriage, if he or she did not have knowledge of that earlier marriage.
A common law marriage however, must involve persons who are legally able to marry each other. In other words, a common law marriage must not involve bigamy.
In both common law marriages and putative marriages, the spouses may be eligible for many of the rights afforded to spouses in real marriages. For instance, they have the right to a fair division of assets, and spousal maintenance. In a common law marriage, the spouses may continue to live together, and must present themselves to the world as a married couple. They must live together as husband and wife. It is important to not just cohabit with each other, but also to enjoy the same rights, duties and privileges of a married couple.
In a putative marriage, the spouses involved may not have that same pressure to “hold themselves up” as a married couple, because they believe that they are in a marriage anyway. The person in a putative relationship turns into a putative spouse, only when he or she discovers that the marriage was not valid all this while.