Two ways to activate a cell phone include contacting the carrier via telephone or bringing the cell to the carrier's retail location. An alternate carrier may be used if it can support the phone. The methods used to activate a cell phone differ between companies.
If the mobile phone has a SIM card, activate it by replacing the card and contacting customer service. The activation process is complete when the phone's carrier appears on the screen along with bars to show reception. A cell phone without a SIM card requires the owner of the device to read the serial number located on the phone's battery.