common law marriage, also known as marriage without formalities or informal marriage, is a valid and legal way for a couple to marry in texas. see the resources below to learn more about common law marriage in texas. texas law does not require the couple to be together for a specific period of time before they can declare themselves to be in a common law marriage. while it is not a requirement, couples can register their common law marriage by filing a declaration with the county clerk. if no declaration was filed and there is a dispute as to whether a common law marriage existed, it may be necessary to go to court in order to prove the marriage. since these types of court proceedings are often complex in nature, it is best to consult with an attorney or a family law practice guide for more information about your options. ending a common law marriage in texas is similar to ending a formal marriage.