Area code 321

Area code 321 is the area code serving Brevard County, Florida. The area code has been in use since November 1, 1999; it was assigned to Florida (instead of suburban Chicago) after a successful petition led by local resident Robert Osband to commemorate the Space Coast's impact on Brevard County. The code refers to the countdown sequence which has launched many spacecraft from Cape Canaveral.

When it was activated in 2000, area code 321 was used as an overlay for most of area code 407 in the Orlando area, except for the small portion of Volusia County that includes Deltona which was in 407 at the time (it is now in 386). However, no (321) numbers were issued in the 407 area from 2003 until 2015, when (321) numbers were issued for cell phones in Orange County due to high demand.

321 is the only area code in North America that is the overlay of one area code, and the sole area code elsewhere. 10-digit dialling is mandatory in both areas.

321 also is the area code used for SatCom Satellite Phone units.Harris/Caprock Corporation has maritime satellite calls going through its corporate call center in Melbourne.

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