Tex. Labor Code § 406.008

(a) An insurance company that cancels a policy of workers' compensation insurance or that does not renew the policy by the anniversary date of the policy shall deliver notice of the cancellation or nonrenewal to the division, and by certified mail, in person, or by electronic means in accordance with Chapter 35, Insurance Code, to the employer, not later than:

(1) the 30th day before the date on which the cancellation or nonrenewal takes effect; or

(2) the 10th day before the date on which the cancellation or nonrenewal takes effect if the insurance company cancels or does not renew because of:

(A) fraud in obtaining coverage;

(B) misrepresentation of the amount of payroll for purposes of premium calculation;

(C) failure to pay a premium when due;

(D) an increase in the hazard for which the employer seeks coverage that results from an act or omission of the employer and that would produce an increase in the rate, including an increase because of a failure to comply with:

(i) reasonable recommendations for loss control; or

(ii) recommendations designed to reduce a hazard under the employer's control within a reasonable period; or

(E) a determination made by the commissioner of insurance that the continuation of the policy would place the insurer in violation of the law or would be hazardous to the interest of subscribers, creditors, or the general public.

(b) The notice required under this section shall be filed with the division.

(c) Failure of the insurance company to give notice as required by this section extends the policy until the date on which the required notice is provided to the employer and the division.