Area code 813 covers all of Hillsborough County, the city of Oldsmar in Pinellas County, and the central and southeastern portions of Pasco County. The northeastern portion of Pasco County is in area code 352, while the western portion is in area code 727.
Area code 813 became Florida's second area code in 1953, when it was split from the state's original single numbering plan area with area code 305. The new number plan area stretched along the Gulf Coast from Pasco County to Collier County and included the cities of St. Petersburg, Sarasota, Fort Myers, and Lakeland.
On March 3, 1996, 13 counties south and east of Hillsborough County, from Manatee County to Collier County, split from the 813 numbering plan area after 43 years in the coverage area and were assigned area code 941.
Although the 1996 split was intended to be a long-term solution, within only two years, 813 was close to exhaustion again because of the rapid growth of telephone service in the Tampa Bay area and the proliferation of cell phones and pagers. The Florida Public Service Commission decided to assign area code 727 as another area code for the region. It was originally planned to be an overlay for the 813 territory. However, overlays were still a new concept, and the mixing of area codes in the same region, and the resulting requirement for ten-digit dialing, met considerable resistance.
In place of an overlay, the area of most of Pinellas County (except Oldsmar) and western Pasco County were split off on February 1, 1999 and received area code 727. Oldsmar kept area code 813 despite being in Pinellas. Oldsmar was a tributary service area to the Tampa area, and tributary routes were in general not cut across NPA boundaries. Oldsmar is also located on the Pinellas/Hillsborough line, and was the only local exchange that was a local call to both cities. Most of the dialup Internet access numbers and alarm system reporting numbers in Tampa and St. Petersburg were located in Oldsmar. GTE and the Florida Public Service Commission wanted to spare alarm companies and ISPs the cost of reprogramming and replacing systems that could not handle 10 digit dialing.
|Florida area codes: 239, 305/786, 321, 352, 386, 407, 561, 727, 754/954, 772, 813, 850, 863, 904, 941|
|West: 727||Area code 813||East: 863|