St. Tammany Parish is a parish located in the U.S. state of Louisiana. As of the 2010 census, the population was 233,740, making it the fifth-most populous parish in Louisiana. The parish seat is Covington. The parish was founded in 1810.
St. Tammany Parish is included in the New Orleans–Metairie, LA Metropolitan Statistical Area. St. Tammany Parish is one of the fastest-growing parishes in the state, along with Livingston and Ascension. Most new residents are thought to have come from St. Bernard Parish.
St. Tammany Parish is colloquially referred to as part of the "Northshore" or "North Shore" throughout metropolitan New Orleans, owing to its location on Lake Pontchartrain. It is the most affluent parish in the metro area, has a nationally recognized system of public schools, and is the most politically conservative parish in the New Orleans region.
The Moon Handbooks New Orleans: Including Cajun Country and the River Road, published in 2007, stated that people wanting to live in proximity to New Orleans without living in New Orleans will probably cause the population of St. Tammany Parish to increase.