The US 183A toll expansion project in Texas, USA is under construction. This work constitutes the third phase of the US 183A toll expansion project of the Central Texas Regional Transportation Authority.

The other two toll lanes will be built at 10.56 kilometers of Section 183A in the U.S. between Leander and Liberty Hills in the north of Austin. The project is expected to cost US$277 million. U.S. Highway 183A provides a bypass for Leander and eases the congestion in the town center, while the original U.S. Highway 183 still carries local traffic.

The third phase of the 183A project is being implemented using the design-bid-build delivery method, and the construction work is under the responsibility of Lion Construction Company. The 183A Phase III project was developed by the Central Texas Regional Transportation Administration in cooperation with some government agencies in Central Texas, including the Texas Department of Transportation (TxDOT), Metropolitan Metro and CAMPO.

In response to population growth in Williamson County, lanes are being added along this part of 183A in the United States. It is estimated that by 2042, traffic in this area will increase by 183%.

U.S. Highway 183 provides an important route for the United States, from Refugio in southern Texas to Prescio in South Dakota. It is worth noting that this is the last road paved in the United States. The last 32 kilometers of Nebraska was only paved in 1967. Editor/Sang Xiaomei