Tex. Occupations Code § 51.401

(a) A person who is otherwise eligible to renew a license may renew an unexpired license by paying the required renewal fee to the department before the expiration date of the license. A person whose license has expired may not engage in activities that require a license until the license has been renewed.

(b) A person whose license has been expired for 90 days or less may renew the license by paying to the department a renewal fee that is equal to 1-1/2 times the normally required renewal fee.

(c) A person whose license has been expired for more than 90 days but less than 18 months may renew the license by paying to the department a renewal fee that is equal to two times the normally required renewal fee. On approval by the executive director, a person whose license has been expired for at least 18 months but less than three years may renew the license by paying to the department a renewal fee equal to two times the normally required renewal fee.

(d) Except as provided by Subsection (c), a person whose license has been expired for 18 months or more may not renew the license. The person may obtain a new license by complying with the requirements and procedures, including the examination requirements, for obtaining an original license.

(e) A person who was licensed in this state, moved to another state, and is currently licensed and has been in practice in the other state for the two years preceding the date of application may obtain a new license without reexamination. The person must pay to the department a fee that is equal to two times the normally required renewal fee for the license.

(f) Not later than the 30th day before the date a person's license is scheduled to expire, the department shall send written notice of the impending expiration to the person at the person's last known address according to the records of the department.