Area codes are how phone companies route your calls to the right geographic location. The 301 area code is one of the original area codes created in North America.
But what area does the 301 area code cover, and why is it historically important? We’ll dive into all of that here.
The history and evolution of area code 301
Area code 301 is one of the original area codes, established in 1947. Back then, it covered the whole state of Maryland.
As populations grew, so did the demand for phone numbers. To meet that demand, area codes were split. In 1991, Maryland’s area code 301 was divided, and the eastern part of the state became area code 410.
Today, area code 301 covers western and southern Maryland, including parts of the Washington, D.C., metro area.
Where is the 301 area code?
The 301 area code covers the state of Maryland, including cities and counties like Germantown, Silver Spring, Bethesda, and Frederick.
Because phone numbers in the 301 area code were running out, the area code 240 was introduced as an “overlay.” This means that 240 covers the same geographic region as 301. So, if you’re in Maryland, you might have a 301 number or a 240 number, depending on when the phone number was assigned.
Why do I have to dial ten digits?
For many years, you could dial just seven digits to call someone in the 301 area code. That changed in 1997, when ten-digit dialing (area code + phone number) became mandatory.
Why the change? Ten-digit dialing is necessary when new “overlay” area codes are introduced. Without it, the phone system wouldn’t be able to tell the difference between calls within the original area code and calls to the new one, which could lead to dropped calls and general confusion.
In Summary
From its start as one of the first area codes to its present-day use, the 301 area code has a long and interesting history. As the original area code for the entire state, it has played an important part in Maryland’s telecommunications story.
Even though technology has changed a lot over the years, the 301 area code continues to be relevant today.