What Value are Cell Phone Number Prefixes?

by : Gloria Moore

Just like with land lines, cell phone numbers assigned in North America all have a set ten-digit length to designate their address in a numerical way. This format was created by AT&T back in 1947 long before the invention of cellular phones, however, its overall layout remains in use today.

This layout is broken down into a 3-3-4 pattern, which refers to the three digits of the number's area code, the three digits of its prefix, and the four digits of the actual line number.

You have likely heard of the area code portion of the number, as it is the segment most commonly referred to by its actual name. It is the three digits assigned by the Federal Communications Commission (FCC) in order to designate the number's location in a given city or portion of a state.

The prefix, however, is less commonly known by its name. It is the first three digits after the area code. The original use of the prefix was to tell the human operator working for the phone carrier to which specific sub-area the telephone number belonged. Naturally, with computerized switches, the prefix is no longer area-specific - especially in the case of cell phones which will work wherever there is a signal, and are not limited by their registered geographical area.

The last four digits belong to the line number, which are the designation for the specific cell phone to which the number was assigned. Though in the case of a land line, several phones can be connected to the same line number, all accessing the same line, cell phones are different. Only one cell phone can use a given telephone number.

Another difference between cell phones and land lines are in the directories for their numbers. Though land lines have complete directories readily available, cell phones numbers don't have a nation-wide or even state-wide directory in which to be listed.