There are a total of 64 counties in the state of Louisiana. Among them, Ascension Parish is the oldest one (established in 1807) while Allen Parish is the youngest (established in 1912). With population of 440,171, East Baton Rouge Parish is the most populated. The biggest county by land area is Plaquemines Parish (6,291 km2) and the smallest is West Baton Rouge Parish (526 km2). Below please see all Louisiana counties which are listed in alphabetical order.
- Acadia Parish, LA
- Allen Parish, LA
- Ascension Parish, LA
- Assumption Parish, LA
- Avoyelles Parish, LA
- Beauregard Parish, LA
- Bienville Parish, LA
- Bossier Parish, LA
- Caddo Parish, LA
- Calcasieu Parish, LA
- Caldwell Parish, LA
- Cameron Parish, LA
- Catahoula Parish, LA
- Claiborne Parish, LA
- Concordia Parish, LA
- DeSoto Parish, LA
- East Baton Rouge Parish, LA
- East Carroll Parish, LA
- East Feliciana Parish, LA
- Evangeline Parish, LA
- Franklin Parish, LA
- Grant Parish, LA
- Iberia Parish, LA
- Iberville Parish, LA
- Jackson Parish, LA
- Jefferson Parish, LA
- Jefferson Davis Parish, LA
- Lafayette Parish, LA
- Lafourche Parish, LA
- LaSalle Parish, LA
- Lincoln Parish, LA
- Livingston Parish, LA
- Madison Parish, LA
- Morehouse Parish, LA
- Natchitoches Parish, LA
- Orleans Parish, LA
- Ouachita Parish, LA
- Plaquemines Parish, LA
- Pointe Coupee Parish, LA
- Rapides Parish, LA
- Red River Parish, LA
- Richland Parish, LA
- Sabine Parish, LA
- Saint Bernard Parish, LA
- Saint Charles Parish, LA
- Saint Helena Parish, LA
- Saint James Parish, LA
- Saint John the Baptist Parish, LA
- Saint Landry Parish, LA
- Saint Martin Parish, LA
- Saint Mary Parish, LA
- Saint Tammany Parish, LA
- Tangipahoa Parish, LA
- Tensas Parish, LA
- Terrebonne Parish, LA
- Union Parish, LA
- Vermilion Parish, LA
- Vernon Parish, LA
- Washington Parish, LA
- Webster Parish, LA
- West Baton Rouge Parish, LA
- West Carroll Parish, LA
- West Feliciana Parish, LA
- Winn Parish, LA