Spanning approximately 16 miles (26 km) along a northwest–southeast axis, it links the cities of Providence, Woonsocket, and Worcester, Massachusetts.

The majority of the route is a freeway, with the exception of at-grade crossings and driveway access in the towns of North Smithfield and Lincoln.

Locally it is known as Old Louisquisset Pike, and is a narrow four-lane freeway with no shoulders and a simple Jersey barrier median separating oncoming traffic.

A stoplight marks the only major intersection, an at-grade crossing with Sayles Hill Road, which doubles back and has a right in/right out interchange with southbound Route 146.

In May 2019, the Rhode Island Senate announced that the state would borrow $200 million to reconfigure I-95 through Downtown Providence, near the southern terminus of Route 146.

[3] In 2022, RIDOT began work on an overpass at Sayles Hill Road, the only set of traffic signals along the route in Rhode Island.

The project also includes constructing service roads and bus bays, and rebuilding the interchange with Route 146A at North Smithfield.

The northern end of the road crosses the state line near Buxton Street at Uxbridge, Massachusetts.