The 240 area code is serving the western part of Maryland, including Maryland's portion of the Greater Washington, D.C. metro area, portions of southern Maryland, along with rural western Maryland.
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Area code 240 covers the western part of Maryland, including the Greater Washington, D.C. metro area, southern Maryland, and rural western Maryland.
Area code 240 is an overlay to area code 301. Area code 301 was the original area code for the entire state of Maryland. Area code 240 was introduced on June 1, 1997. A third overlay code, 227, was added on June 14, 2023. Ten-digit dialing is required for all calls within this region.
Area code 240 is a general purpose code which was placed in service on June 1, 1997.
Our Maryland phone number lookup service will analyze the three-digit prefix of any 240 area code phone number and will show which telecommunications company and rate center it was initially assigned to. This prefix code data may help to determine the U.S. carrier, Maryland geographic region, and local calling area associated with the phone number.
Phone numbers follow the following structure under the North American Numbering Plan:
Understanding the area code can help you determine if a call is local to your area. However, keep in mind that due to mobile number portability and VoIP services, the caller may be anywhere in the United States, so it’s best to search for the most recent phone number details.
| Company | Number of Prefixes |
|---|---|
| SPRINT SPECTRUM, L.P. | 54 |
| CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD | 45 |
| VERIZON MARYLAND, INC. | 42 |
| NEW CINGULAR WIRELESS PCS, LLC - DC | 41 |
| OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 24 |
| LEVEL 3 COMMUNICATIONS, LLC - MD | 21 |
| XO MARYLAND, LLC | 20 |
| US LEC OF MARYLAND, INC. | 16 |
| GLOBAL CROSSING LOCAL SERVICES, INC. - MD | 12 |
| CAVALIER TELEPHONE MID-ATLANTIC, LLC - MD | 10 |
| STARPOWER COMMUNICATIONS, LLC - MD | 10 |
| MCIMETRO ACCESS TRANSMISSION SERVICES LLC | 9 |
| CAVALIER EAST, LLC - MD | 8 |
| COMCAST IP PHONE, LLC | 7 |
| ONVOY, LLC - MD | 6 |
| PAETEC COMMUNICATIONS, INC. - MD | 6 |
| PEERLESS NETWORK OF MARYLAND, LLC | 6 |
| TELEPORT COMMUNICATIONS AMERICA, LLC - DC | 5 |
| BANDWIDTH.COM CLEC, LLC - MD | 4 |
| CORE COMMUNICATIONS, INC.- MD | 4 |
| SPRINT SPECTRUM, LP - MD | 4 |
| ATX COMMUNICATIONS SERVICES, LTD. | 2 |
| LIGHTWAVE COMMUNICATIONS, LLC - MD | 2 |
| LOCAL ACCESS LLC - MD | 2 |
| NUSO, LLC | 2 |
| YMAX COMMUNICATIONS CORP. - MD | 2 |
| AT&T - LOCAL | 1 |
| BALTIMORE-WASHINGTON TELEPHONE (BWT) | 1 |
| LEVEL 3 TELECOM OF MARYLAND, LLC - MD | 1 |
| MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD | 1 |
| METROPCS, INC. | 1 |
| PAETEC COMMUNICATIONS, INC. - DC | 1 |
| TELEPORT COMMUNICATIONS AMERICA, LLC - MD | 1 |
Carrier names have been updated from their original FCC assignments to reflect current companies following mergers, acquisitions, and rebranding. Updates were determined using AI-assisted research and may not be accurate or reflect up to date changes. This data is provided without warranties of accuracy or completeness.
| Rate Center | Number of Prefixes |
|---|---|
| WSHNGTNZN3 | 56 |
| WSHNGTNZN2 | 45 |
| WSNGTNZN10 | 36 |
| GAITHERSBG | 30 |
| FREDERICK | 25 |
| WALDORF | 18 |
| LAUREL236 | 17 |
| WSHNGTNZN4 | 14 |
| HAGERSTOWN | 13 |
| WSHNGTNZN5 | 12 |
| ASHTON236 | 10 |
| WSNGTNZN11 | 10 |
| LEONARDTN | 9 |
| WSNG236Z13 | 9 |
| WSNG236Z14 | 8 |
| CUMBERLAND | 7 |
| LAUREL238 | 6 |
| LXTNPKGRML | 5 |
| WSNGTNZN12 | 5 |
| WSHNGTNZN6 | 4 |
| ASHTON238 | 3 |
| BUCKEYSTN | 3 |
| DAMASCS236 | 3 |
| INDIANHEAD | 3 |
| MYERSVILLE | 3 |
| MECHANCSVL | 2 |
| NANJEMOY | 2 |
| WSNG236Z15 | 2 |
| WSNGTNZN16 | 2 |
| HUGHESVL | 1 |
| LA PLATA | 1 |
| MIDDLETOWN | 1 |
| MOUNT AIRY | 1 |
| OAKLAND | 1 |
| RIDGE | 1 |
| WILLIAMSPT | 1 |
| WSNG238Z13 | 1 |
| WSNG238Z14 | 1 |
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