Welcome to CoServ Gas—providing outstanding Customer service and safe natural gas delivery to you is our privilege. This section contains important details about your rights and responsibilities as our Customer. If you have questions about your service or billing, please login to your online CoServ account or call us at (940) 321-7800. If you have a natural-gas emergency, call 911. You can also contact CoServ Gas 24/7 through our toll-free emergency number, (800) 274-4014.