From the southeast, LA 81 begins at an intersection with LA 77 in Livonia. LA 77 heads southeast toward Maringouin, eventually reaching I-10, and connects to US 190 immediately to the north. LA 81 proceeds westward out of Livonia, running parallel to US 190, and crosses the Union Pacific Railroad tracks at grade. later, LA 81 passes through an area known as Blanks and intersects LA 976, a short connector to US 190. Continuing west for, LA 81 curves to the north briefly and enters the small community of Lottie. It then curves back to the west and becomes known as Old State Highway. LA 81 turns north opposite the Lottie post office and proceeds a short distance across a second grade crossing with the UPRR to an intersection with US 190. US 190 connects to Baton Rouge on the east and Opelousas on the west. LA 81 proceeds north across US 190 and away from Lottie. Now known as Charles Road, LA 81 begins to take a more winding route, closely following the remains of Bayou White. later, LA 81 curves to the east and enters the northwest corner of Fordoche. It ends shortly afterward at a second intersection with LA 77, the main highway through town. To the north, LA 77 connects with LA 10 to Morganza. The route is classified as a rural local road by the LouisianaDepartment of Transportation and Development. Average daily traffic volume in 2013 is reported as 410 vehicles between Livonia and Lottie, increasing to 1,060 between Lottie and Fordoche. The posted speed limit is in Livonia, in Lottie and Fordoche, generally increasing to between points. LA 81 is an undivided, two-lane highway for its entire length.
The southern section running from Livonia west to Lottie was a small part of State Route 7, which was designated in 1921 by an act of the state legislature. Route 7 was originally an important cross-state route known as the Evangeline Highway and generally followed the modern US 190 corridor. The section that is now LA 81 served as part of the main highway between Baton Rouge and Opelousas until it was bypassed by the Airline Highway in 1933. Two years later, the new route became part of US 190, which was extended west into Texas from its original terminus at the Mississippi River in Baton Rouge. Most of the old road running west from Lottie to the Atchafalaya River opposite Krotz Springs was abandoned shortly afterward. As was often the case during this era, the state highway department did not move the Route 7 designation onto the new highway. As a result, Route 7 became discontinuous and served as little more than a local road in the area until the 1955 Louisiana Highway renumbering.
Northern section
The remaining section of the current LA 81, running northward from Lottie to Fordoche, was designated as State Route C-1943 prior to the 1955 renumbering. It was created in the 1940s and, like all routes added after 1930, it was numbered by the state highway department rather than by the state legislature and carried a "C-" prefix.
Post-1955 route history
LA 81 was created in 1955 as a collective renumbering of the surviving portion of former State Route 7 between Lottie and Livonia as well the entirety of former State Route C-1943. With the 1955 renumbering, the state highway department initially categorized all routes into three classes: "A", "B", and "C". The northern section of LA 81 was categorized as Class "B" and the southern section as Class "C." This system has since been updated and replaced by a more specific functional classification system that now designates the entire route as a rural local road. However, the route of LA 81 has remained the same to the present day.
Future
La DOTD is currently engaged in a program that aims to transfer about of state-owned roadways to local governments over the next several years. Under this plan of "right-sizing" the state highway system, the entire route of LA 81 is proposed for deletion as it does not meet a significant interurban travel function.
