SACRAMENTO (CBS13) – Get ready to dial more digits; big changes are coming to the 916 area code this weekend.

Starting Saturday, people using a landline will have to dial a “1” then the area code for a call to go through.

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People in the 916 area code who sign up for a new number starting March 10 will be given a new 279 area code.

People with existing 916 numbers will not need to change their number.

People using cellphones will have to dial the area code, but not a “1” first. Cellphone users will also need to add the area code to their stored contacts.

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The new ten-digit calls also requires reprogramming of services tied to phone numbers, like life safety systems, medical monitoring systems, security systems, and fire and burglar alarms.

“If their panel isn’t updated or replaced, they’re going to find out they no longer have protection,” said Tim Sproul, president and CEO of Total Monitoring Services.

Dialing ten digits will become mandatory on Saturday or your calls will drop and you’ll receive a message to hang up and dial again.

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The Public Utilities Commission approved the 279 overlay to the 916 area code last February.