[5] When it became financially unfeasible to construct the entire route with public funds within a reasonable timeframe, it was decided that the remaining portion of the route (approximately two-thirds of the total completed mileage) would be constructed as a toll road and designated as a North Carolina highway rather than an Interstate Highway.

When completed, the beltway will total 70 miles (110 km) in length, surrounding the city of Raleigh and the towns of Apex, Cary, Garner, and Morrisville.

interchange, I-540 has its western terminus at I-87/US 64/US 264 (exit 26), though the roadway continues on for a short distance, and several ghost ramps indicate the planned connection to the rest of the loop.

Several gantries are located along the route and entrance/exit ramps, where they collect toll via the NC Quick Pass or other interoperable ETC systems.

In the mid-1980s, realizing that the growth in western Wake County may require more roads than planned, highway planners decided to expand the project as a new beltway around Raleigh.

Officials decided to change the designation in early July at the urging of the North Carolina Turnpike Authority (NCTA).

Work on the western and southern portions of the beltway, if paid for by state funds, would possibly not open until 2030.

At the request of several Wake County mayors, the NCTA in 2006 began studying the use of tolls to complete these portions of the Outer Loop.

The Authority concluded in early 2007 that it would be financially feasible to build the western section (along with an extended Durham Freeway, which combined would be called the "Triangle Expressway") using toll funds.

[35] On August 1, 2012, the first phase of the Western Wake Freeway opened, connecting NC 55 in Morrisville (exit 66) to US 64 in Apex.

[36] On April 3, 2017, the Veridea Parkway interchange (exit 55; formally known as Old Holly Springs Apex Road) was opened to traffic.

[30][43] After two years, the General Assembly chose to permit studying the Red Corridor, which meant possible routes could once again be considered.

[49] However, Tropical Storm Debby, reportedly, caused significant erosion along the unopened portion of the expressway further delaying the opening to vehicles.

[42] A plan approved by the Raleigh city council in November 2013 includes asking for tolls for the existing highway in order to widen it to eight lanes by 2035 or 2040.

As a temporary solution to increased traffic on the northern section, NCDOT has installed ramp meters on some onramps, the first ones in the state.

Public input over the growth and development of a 15,000-acre area of eastern Wake County along the lower Neuse River as well as the future southern loop of NC 540 was requested on June 23, 2023.

[55][56] The process of completing the final segment was sped up after the N.C. Turnpike Authority (NCTA) was able to get a single environmental permit, allowing for utility work to begin.

That coupled with strong local support and expected toll revenues moved the project up NCDOT's list of priorities and the bidding process for the segment began much earlier than anticipated in Summer 2023.

[58] In September 2023, it was announced that Flatiron-Fred Smith Company Joint Venture had been awarded a $450 million contract to complete the first segment;[57][58][59] S.T.

[58][60] In December 2023, the Local Government Commission (LGC) approved an application by the NCTA for revenue bonds and a Transportation Infrastructure Finance & Innovation Act (TIFIA) loan through US-DOT to start construction.