Area Code, Prefix, & Other Parts of a Phone Number

Did you ever wonder where the digits in your phone number come from, and what they mean? As you probably suspected, each segment has a reason for being there.

Like most codes, it contains information in each part that allows it to function properly and to send your call to the right place. If you dial a phone number using even one digit more or less than the exact code (we’ve all tried it), then you quickly find that it simply doesn’t work.

While we take it for granted that phone numbers work and don’t really think about how this number connects our call, the system is made possible by those groups of numbers working together in just the right way.

Now you can finally understand what each part of the phone number means, and what it does.

Call it Like it Is

First things first—let’s name each part of a phone number, and then we’ll get into their respective functions.

The first grouping is of course, the area code. The area code is the identifier for a geographic region.

The next grouping is the 3-digit prefix, which narrows the location of the phone number a little further.

Finally, there is the line number. These are the last 4 digits of the phone number which directs a call to a specific phone line.

country codes

Country Code

The “+1”, or country code is the first thing you dial to reach a phone line anywhere else in the country. It is usually not required when dialing between phone numbers that are registered in the same geographic region—that is, two numbers that have the same area code.

These are different for other countries, but the “1” preceding our numbers is the country code for the United States and Canada.

Now let’s take a closer look at how each code functions.

area codes

Area Code

Area codes bring a call to the larger geographic region which may contain multiple towns; at the same time, large cities generally have multiple area codes.

There are two basic types of area codes: Local and Toll Free. Toll free area codes are 800, 844, 855, 866, 877, and 888; local area codes are all the other ones.

Then of course, there is the 900 area code which represents a “toll” number, or “pay-per-call”, which many of us remember as the rather conspicuous area code.


After the area code, you have the prefix. The prefix expectedly provides a more narrowed location of a telephone number, signifying a specific location such as a town.

The area code generally does not need to be dialed when calling another number with the same prefix.

vanity number

Line Number

The line number is the final and most specific code of the phone number. This code provides an exact address for connecting the call with a specific phone line.

If you are looking for a vanity number for a business, the line number is the best section to form it because there are more combinations available, and you’re more likely to get the number you want.

Each section of a telephone number from country code, to line number, brings a call incrementally closer to the destination until it reaches the phone you’re calling.

From the time you dial the last digit to the time the receiver picks up the call is only a few seconds—so it’s a pretty efficient system, even with decades-old infrastructure like the PSTN (original wired network).

A telephone number puts your call straight through to the receiver, like following a street address to someone’s doorstep.


Stephanie is the Marketing Director at Talkroute and has been featured in Forbes, Inc, and Entrepreneur as a leading authority on business and telecommunications.

Stephanie is also the chief editor and contributing author for the Talkroute blog helping more than 100k entrepreneurs to start, run, and grow their businesses.

StephanieArea Code, Prefix, & Other Parts of a Phone Number