SAN FRANCISCO (CBS SF) — If you’re moving to San Francisco, good luck finding affordable housing, and now a 415 area code. The classic three number prefix for Marin and San Francisco has run out of capacity and starting next month, will no longer be assigned to new numbers.

As of February 21, the new 628 area code ‘overlay’ goes into effect and callers must use the new 1 + 10-digit dialing procedure for all calls. After that date, if customers do not use the new dialing procedure, their calls will not be completed and a recording will instruct them to hang up and dial again.

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Then starting on March 21, new telephone lines and services in the 415 area will be assigned numbers using the new 628 area code.

Increasing consumer demand prompted the Public Utilities Commission to add the 628 area code to the region that has been using 415 since 1947. That’s San Francisco, most of Marin County, and a small portion of San Mateo County.

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The CPUC is advising customers to reprogram speed dials with a seven-digit number in order to follow the new complete dialing procedure for a local number. It’s akin to making a long distance call, however local rates remain the same.

The new rule will not effect people dialing 9-1-1 to report an emergency.

You can view the Overlay Map for complete information on areas affected.

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