TDSP stands for Transmission and Delivery Service Provider. These utilities own the poles and wires that deliver electricity to homes and businesses. They also own the meter that tracks electricity usage, and provide the usage information for monthly billing.
In the deregulated areas of Texas, where consumers sign up with a Retail Electricity Provider (REP), the TDSP bills the REP for their fees, and the REP will pass this on to the consumer. Sometimes called Delivery Charges, these fees are regulated by the Texas Public Utilities Commission. TDSP charges differ, depending on where you live, but you can find the charges at the top of the EFL for any plan.