No. When you’ve chosen a new deal, your new supplier will handle the switching process. They’ll contact you to let you know what date you’ll be transferred over, and they’ll contact you around the switching date to ask for a meter reading. They’ll pass this on to your old supplier so they can send you a final bill. You don’t need to contact your old supplier, as the new supplier will handle everything for you.
An additional bill was passed in 1999 that helped further establish a competitive electricity market by creating a price floor to prevent established energy providers from underselling emerging providers. In 2002, Texas finalized deregulation when the Public Utility Commission gave ERCOT the responsibility of managing and monitoring the Texas electricity market. The market opened up to around 6 million Texas power customers.