Area code 210 With ZIP CODE (78101 – 78073)

Area code 210 is a North American telephone area code for numbers in and near San Antonio, Texas. It is an enclave area code, similar to area code 312 in Chicago, area code 213 in Los Angeles, area code 316 in Wichita, Kansas and area codes 385/801 in Salt Lake City, in that it is completely surrounded by area code 830.

It was created November 1, 1992, in a split from area code 512. Before that date, 512 had served the entire south-central portion of Texas since the area code system was instituted in 1947; 512 was the last of Texas’ original four area codes to be split.

The formation of 210 was intended to be a long-term solution in order to relieve exchanges in the Austin–San Antonio corridor. However, within four years 210 was already close to exhaustion because of San Antonio’s rapid growth and the popularity of cellular telephones and pagers. This forced a three-way split, which took place on July 7, 1997.

Most of Bexar County stayed in 210, while the San Antonio suburbs and the Texas Hill Country were split off as area code 830. The southern portion became area code 956. The 1997 split made San Antonio one of the few cities that are split between two area codes, as well as being the largest city in Texas where 7-digit dialling is still possible. Some portions of San Antonio located in Medina and Comal counties, as well as a few portions of Bexar County, are now in 830.

At this time, 210 is expected to exhaust once again by mid 2018, around which time an overlay of 210 (including the switch to ten-digit dialling) will be implemented. Planning for that new area code began in June 2015. The new overlay code will be 726.