Barangay San Carlos is also part of the South District Division of Barangays in Tarlac City. Barangay Dela Paz and San Francisco bound it on the North, Barangay Armenia on the West, Barangay Burot on the East and Municipality of Capas on the South.

It is approximately 10.6 kilometers away from city proper. It has total land area of 205.23 hectares wherein the 165.05 hectares correspond to agricultural area and the remaining 39.73 hectares designate to residential area and commercial area. It is also divided into seven Purok namely: Purok 1, Purok 2, and Purok 3 to Purok 7.

Barangay San Carlos classified as Rural Barangay, it has a total population of one thousand two hundred eighty seven (1,287) as of 2005, and a household population of two hundred fifteen (215).

One of the major sources of livelihood of many people residing in this area was farming. They cultivate palay, corn, vegetables and so on. Some of the residents were employees, laborers, drivers, construction workers and others. Others acquired their needs on their mini business stall such as sari sari stores and so on.

Before the arrival of the Japanese and Americans in the province, Barangay San Carlos is already an established barangay “Mambog” that was the former name of this Spanish established barangay. This place was once a forested area with tree growing abundantly in the area and Mambog trees grew here. The name Mambog only abolished when the first barangay Captain of the said place bought a Patron Saint from San Carlos City Pangasinan. And right after that, it was renamed after their Patron Saint Carlos. Baun, Sundiang, Canlas, and Manuel Family was among the early settlers of this barangay.

Eighty percent of the total populations are Pampango, and the rest are Tagalog, Bisaya, Pangasinense, and Ilocano.

Barangay San Carlos celebrates their feast day every November 03-04 as a thanksgiving to their Patron San Carlos. Saint Charles Borromeo (Italian: Carlo Borromeo; Latinized as Carolus Borromeus) (October 2, 1538 – November 3, 1584) was an Italian saint and cardinal of the Roman Catholic Church.