From the west, LA 433 begins at a junction with U.S. Route 190 (US 190) near the North Shore Square mall and heads south.

As the road nears downtown Slidell, it crosses Bayou Bonfouca via a drawbridge and becomes a four-lane divided highway.

Shortly thereafter, the road joins US 11 and heads southward for about a quarter of a mile before departing eastward along the Old Spanish Trail.

Heading southeastward, the highway is duly known as Rigolets Road and the Old Spanish Trail at this point.

The route then widens to an undivided, five-lane roadway (with a middle turning lane) while concurrent with US 11.