By filing a mechanic's lien, you can hold clients accountable with the backing of Texas law. Learn more about mechanic's liens in Texas.Need to file a mechanics lien in Bexar County? Find everything you need to file your lien with the Bexar County Clerk here. This howto guide provides a starttofinish explanation on how to file a Texas mechanics lien and even includes free downloads of important forms. A lien is a claim against someone's property that allows a nonowning party to hold an interest in the property until the owner repays a debt. For a residential construction project, you must file the lien affidavit no later than the 15th day of the 3rd month after the day the indebtedness accrues. A property lien is a legal claim against a piece of personal or real property due to contractual or statutory obligations. The request for notice of termination or abandonment must already have been given to the owner. A constitutional lien is self-executing.