SAN FRANCISCO (KCBS) – KCBS Radio is getting reports that Sprint customers in the 415 area code are already having to dial out the area code to make a local cell call.

The area code dialing change isn’t scheduled to start until midnight. But some Sprint cell phone customers with a 415 area code are already getting an error message. Customers with other carriers don’t appear to be affected.

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“We are looking into the matter.  In preparation for the 415 area code overlay, Sprint did provide customers ample notice via billing inserts, postcards and website detailing required dialing procedures,” Sprint Communications Manager Caroline Semerdjian said in a statement to the station.

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The dialing change – which just affects 415 numbers – is the result of the start of a second area code – 628 – for new accounts in San Francisco and Marin. Starting Friday night, all 415 callers will need to dial out the full number for all calls.

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