How do electronic toll tag systems in Texas work interchangeably?

In Texas, toll roads are operated by state, regional or county authorities, according to the Texas Department of Transportation.

In the Austin area, TxDOT-operated toll roads use the TxTag system.

The Dallas area’s North Texas Tollway Authority, which is a political subdivision sanctioned by the state, uses the TollTag system.

The Harris County Toll Road Authority and Fort Bend County Toll Road Authority operate toll roads in the Greater Houston area using the EZ Tag system.

Despite the different toll-collection systems in the state, a toll tag for any one of the three entities works interchangeably for the other two systems.

Payments are automatically deducted from a user’s account each time a driver passes under a toll gantry as long as the driver has a toll tag. Drivers without a toll tag will be billed separately by each tolling authority.