It runs 173.41 miles (279.08 km)[2] in a northwest to southeast direction from LA 29 in Whiteville to U.S. Highway 90 (US 90) north of Raceland.

Additionally, the former US 90 alignment between Lafayette and Raceland was once part of the earlier Old Spanish Trail and is still known as such in many places along the route.

South of Opelousas and an area known as Shuteston, LA 182 turns to the east into Sunset and the adjacent Grand Coteau.

LA 182 curves to the southeast, enters the city of Lafayette, and intersects I-10/US 167 between Lake Charles on the west and Baton Rouge on the east.

[3][6][7] From the junction with I-10, LA 182 shares a concurrency with I-10 and US 167 eastward to the intersection with southern terminus of I-49 and the Evangeline Thruway.

[8] Eastbound LA 182, which is the west frontage road, curves southeast under US 90 along the BNSF/Union Pacific Railroad tracks.

[3][6][9] In St. Mary Parish, LA 182 passes through Baldwin and Franklin, cutting across some wide bends in Bayou Teche.

Southeast of Franklin at a point known as Calumet, LA 182 briefly joins US 90 across the Wax Lake Outlet bridge.

In Berwick, LA 182 again connects with US 90 but maintains its own parallel bridge crossing over the Lower Atchafalaya River/Berwick Bay into Morgan City.

After crossing Bayou Boeuf, LA 182 passes briefly through the southern tip of Assumption Parish.

It was subsequently extended southeast over former sections of US 167 and US 90 bypassed by newer, four-lane alignments (built under the temporary designation of LA 3052).

LA 182 replaced these routes upon its final extension in 1999 with the completion of the US 90 freeway between Morgan City and Raceland.

It was part of LA 182 until a portion of the route in Broussard was transferred to local control in 2015, creating a gap in state maintenance.

[17] LA 182-1 was decommissioned on July 18, 2022 after ownership of Pinhook Road was transferred from the LADOTD to the cities of Lafayette and Broussard.

Louisiana Highway 182-2 (LA 182-2) ran 1.342 miles (2.160 km) in a north-south direction from the junction of South De Porres Street in Broussard to a junction with St. Etienne Road and LA 182 eastbound on the west side of the US 90 freeway.

It was part of LA 182 until a portion of the route in Broussard was transferred to local control in 2015, creating a gap in state maintenance.

Past 2nd Street, LA 182-2 curved south, paralleling US 90 to the east, before arriving at a junction with Albertson Parkway.

Southeast of this intersection, northbound LA 182 can be reached via a turnaround lane underneath the US 90 railroad overpass.