240 Area Code

Area Code Overview

Area code 240 is a geographic telephone area code in Maryland that went into service on June 1, 1997. The geographic regions covered by this area code overlay has a population of approximately 1,658,076.

Overlay and Dialing Rules

  • Area Code: 240
  • State: Maryland
  • Type: General Purpose Code
  • In Service Date: June 1, 1997
  • Overlay Complex: 227/240/301
  • Local Dialing Plan: This area does require you to dial the area code when calling locally.

Estimated Number of Assigned Phone Numbers in Area Code 240

This area code is ranked 234th out of 363 nationwide in estimated assigned phone numbers. Within the state territory it serves, it is ranked 3rd out of 6.

3,820,000

Estimated Service-Type Mix of Assigned Phone Numbers in Area Code 240

Total assigned 3,820,000
Wireless
1,436,000 assigned
37.59%
Wireline and VoIP
1,895,000 assigned
49.61%
Other / Unclassified
489,000 assigned
12.80%

Estimated Share of Wireless Numbers Originally Assigned to Each Carrier in Area Code 240

Estimated assigned wireless phone numbers: 1,436,000

Numbers may later be ported to another carrier, but this chart reflects original number assignment, not current subscriber share.

T-Mobile 578,000 (40.25%)
AT&T Wireless 432,000 (30.08%)
Verizon Wireless 426,000 (29.67%)

Estimated Share of Wireline and VoIP Numbers Originally Assigned to Each Carrier in Area Code 240

Estimated assigned wireline and VoIP phone numbers: 1,895,000

Onvoy 576,000 (30.40%)
Bandwidth 299,000 (15.78%)
Spectrum 160,000 (8.44%)
Lumen 143,000 (7.55%)
Comcast Business 126,000 (6.65%)
Peerless Network 112,000 (5.91%)
VERIZON MARYLAND, INC. 103,000 (5.44%)
MCIMETRO ACCESS TRANSMISSION SERVICES LLC 76,000 (4.01%)
Telnyx 60,000 (3.17%)
PAETEC ITEL, LLC 51,000 (2.69%)
MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 38,000 (2.01%)
YMAX COMMUNICATIONS CORP. - MD 35,000 (1.85%)

Other / Unclassified Assigned Numbering in Area Code 240

Estimated assigned other or unclassified phone numbers: 489,000

CORE COMMUNICATIONS, INC.- MD 344,000 (70.35%)
TELEPORT COMMUNICATIONS AMERICA, LLC - MD 57,000 (11.66%)
TON80 COMMUNICATIONS, LLC 22,000 (4.50%)
IP HORIZON LLC 15,000 (3.07%)
USCOC OF CUMBERLAND, INC. DBA UNITED STATES CEL MD 12,000 (2.45%)
HD CARRIER LLC 10,000 (2.05%)
IDT AMERICA, CORP. - MD 10,000 (2.05%)
SHENTEL COMMUNICATIONS, LLC. - MD 5,000 (1.02%)
BARR TELL USA, INC. 4,000 (0.82%)
FRACTEL, LLC 4,000 (0.82%)
CORETEL MARYLAND, INC. - MD 2,000 (0.41%)
TELEPORT COMMUNICATIONS AMERICA, LLC - DC 2,000 (0.41%)

How These Figures Were Built

These figures are estimates based on public phone-number assignment records. They are meant to show the likely mix of assigned phone numbers associated with area code 240, not live customer counts.

Some providers may have assigned phone numbers tied to this area code even if they do not actively market or sell service locally. These figures reflect public number-assignment records, not confirmed local service availability.

They also do not reflect number portability at the individual phone-number level, so some numbers may now be used on a different network or by a different provider than the original assignment records suggest.

Population data and locality matching provided by GeoNames.

Last refreshed: April 15, 2026 6:22 pm