Search Tax ID. Use the 11-digit Comptroller's Taxpayer Number or the 9-digit Federal Employer's Identification Number. Online filing and searching available through SOSDirect.For information or to subscribe, call (512) 475-2703. If you need to close a business location that you no longer operate or end your sales tax responsibility completely, please use the form below. You'll want to choose a business name that reflects your brand identity and doesn't clash with the types of goods and services you offer. Review our Frequently Asked Questions below. If you need additional assistance, please contact us. The Intergovernmental Relations Office manages the process for these appointments following the procedures laid out in the Uniform Appointment Policy. A list of other services is also available on our portal. Parent List With Company Names (Index (American Business Locations Directory) (v.