Q: How to establish a common law marriage posthumously in Texas?

A: From your question, it does not sound like you meet the legal requirements for a common law marriage in Texas.

Assuming that you and your fiancé did not file a Declaration of Informal Marriage with the county clerk, you would have to satisfy three legal requirements:

1) You will have to show an agreement to presently be married, not to get married in the future. Indeed, evidence of having gotten a marriage license and setting a wedding date affirmatively negate this required element.

2) You would have to show that after reaching that agreement, you and your fiancé lived together as spouses. you have plenty of evidence of living together, probably even before your engagement. You even purchased a home together as tenants in common. But you can't show that happened AFTER such an agreement.

3) You would have to show that after reaching that agreement, you and your fiancé both publicly held each other out as spouses in some meaningful manner. Filing joint federal income tax returns is often considered prima facie evidence of this element but is not necessarily dispositive. Filing separate federal income tax returns as single person is evidence negating this element. Other evidence can also be offered. For example, listing each other as spouses on health insurance, medical records, bank accounts, retirement accounts, etc. can be persuasive evidence. Weaker evidence would be testimony of co-workers, neighbors, and friends that both of you publicly introduced each other as spouses.

For purposes of inheritance, you would file an application to probate your fiancé's Will or estate in probate court and ask to be declared his heir at law by virtue of marriage. It should be cautioned that the probate court's determination of the existence of a common law marriage is not necessarily binding on people or entities that are not directly involved in the probate of your fiancé's Will or estate. For other purposes, you can file a suit for declaratory judgment naming applicable people or entities who have an interest in whether you are his spouse or not. Be aware that creditors can use a determination in another proceeding that you ARE his common law spouse against you under the doctrine of collateral estoppel to collect certain types of debts (like medical bills, certain taxes, etc.) because you were a participant in that proceeding even if they were not.