CallataGuidesArea code 240
Where 240 is, how it is dialed, which carriers hold its numbers and how many of its codes are in use, from NANPA's 10/01/2026 files.
- State
- MD
- In service
- 1997
- Assigned codes
- 785of 800 possible
- Carriers
- 43
About area code 240
NANPA lists 240 as an in-service geographic area code for Maryland, first put into service on June 1, 1997. It is an overlay: 240 and 227 and 301 cover the same territory, so neighbors on the same street can have different area codes. It is in the Eastern time zone. The places with the most assigned exchanges include Frederick, Gaithersburg, Hagerstown, Leonardtown, and Cumberland. By population, its largest named places are Frederick, Gaithersburg, Hagerstown, Cumberland, and La Plata.
| Item | Value |
|---|---|
| State | Maryland |
| In service since | June 1, 1997 |
| Assigned by NANPA | June 21, 1996 |
| Overlay | Yes, with 227, 301 |
| Parent area code (NANPA) | 301 |
| Time zone | Eastern |
| Local calls within the code | ten digits (area code plus number) |
| Assigned central office codes | 785 |
| Rate centers with codes | 63 |
| Carriers holding codes | 43 |
| Pooled codes | 727 |
| Codes assigned since 2020 | 132 |
| Relief planning in progress | No |
Source: NANPA NPA report and utilized central office code file, both dated 10/01/2026.
Where 240 numbers are local
240 holds 21% of the 3,730 central office codes assigned in Maryland, the most of any code in the state. 28 Census places could be matched to rate centers with 240 exchanges; the most populous are Frederick (89,537), Gaithersburg (70,686), Hagerstown (43,909), and Cumberland (18,643). For a storefront or service area inside 240, the place pages show which prefixes are rated local there.
| Place | Population (2024) | Area codes | Exchanges | Carriers |
|---|---|---|---|---|
| Frederick, MD | 89,537 | 227, 240, 301 | 88 | 20 |
| Gaithersburg, MD | 70,686 | 227, 240, 301 | 80 | 19 |
| Hagerstown, MD | 43,909 | 227, 240, 301 | 57 | 24 |
| Cumberland, MD | 18,643 | 227, 240, 301 | 31 | 13 |
| La Plata, MD | 11,374 | 240, 301 | 11 | 9 |
| Mount Airy, MD | 9,914 | 227, 240, 301 | 8 | 7 |
| Brunswick, MD | 9,015 | 227, 240, 301 | 5 | 5 |
| Frostburg, MD | 6,972 | 240, 301 | 6 | 5 |
| Walkersville, MD | 6,535 | 240, 301 | 5 | 5 |
| Thurmont, MD | 6,308 | 227, 240, 301 | 5 | 3 |
| Poolesville, MD | 5,856 | 240, 301 | 8 | 7 |
| Middletown, MD | 5,055 | 227, 240, 301 | 6 | 4 |
| Leonardtown, MD | 5,041 | 227, 240, 301 | 28 | 13 |
| Indian Head, MD | 4,247 | 240, 301 | 12 | 8 |
| Smithsburg, MD | 3,194 | 227, 240, 301 | 5 | 5 |
Population: Census Vintage 2024 estimates for the matched place. Exchanges and carriers: NANPA utilized code file.
Dialing 240 numbers
According to NANPA's dialing-plan data, local calls within 240 are dialed as ten digits (area code plus number) and toll calls as 1 plus ten digits. Ten-digit local dialing means the area code is part of how customers save and recognize your number, so print it in full everywhere. NANPA's dialing-plan note for this code reads: "1+10 digit dialing for all calls permissible at service providers discretion."
Who holds 240 exchanges
43 carriers hold the 785 central office codes assigned in 240. Omnipoint Communications Cap Operations, LLC has the most, with 117 (15%). 727 of the codes (93%) are pooled, meaning the code holder shares blocks of 1,000 numbers with other carriers instead of using all 10,000 itself. Numbers can move between carriers through porting, so a code's holder tells you where the block started, not where every number lives now.
| Carrier (NANPA operating company) | Exchanges | Share |
|---|---|---|
| Omnipoint Communications Cap Operations, LLC | 117 | 15% |
| Cellco Partnership d/b/a Verizon Wireless - MD | 85 | 11% |
| New Cingular Wireless PCS, LLC - DC | 69 | 8.8% |
| Paetec Itel, LLC | 63 | 8.0% |
| Level 3 Communications, LLC - MD | 59 | 7.5% |
| Onvoy, LLC - MD | 56 | 7.1% |
| Verizon Maryland, INC. | 48 | 6.1% |
| Mcimetro Access Transmission Services LLC | 46 | 5.9% |
| Peerless Network of Maryland, LLC | 42 | 5.4% |
| Bandwidth.com CLEC, LLC - MD | 35 | 4.5% |
| Core Communications, Inc.- MD | 32 | 4.1% |
| Metropcs, INC. | 21 | 2.7% |
Carrier names are the operating company (OCN) names on NANPA's utilized central office code file dated 10/01/2026. A carrier holding a code may port numbers to other carriers.
Local calling areas in 240
NANPA assigns each central office code to a rate center, the local calling area that decides whether a call is local or toll. 240 has codes in 63 rate centers. The table lists the rate centers with the most codes, with the matching Census place where the abbreviation could be matched.
| Rate center (NANPA) | Place | Codes |
|---|---|---|
| WSHNGTNZN3 | not matched | 73 |
| WSHNGTNZN2 | not matched | 64 |
| WSNGTNZN10 | not matched | 54 |
| FREDERICK | Frederick, MD | 43 |
| GAITHERSBG | Gaithersburg, MD | 40 |
| LAUREL236 | not matched | 39 |
| HAGERSTOWN | Hagerstown, MD | 33 |
| WSHNGTNZN4 | not matched | 30 |
| WSHNGTNZN5 | not matched | 28 |
| WALDORF | not matched | 26 |
| ASHTON236 | not matched | 25 |
| WSNG236Z13 | not matched | 18 |
| WSNGTNZN11 | not matched | 17 |
| LEONARDTN | Leonardtown, MD | 17 |
| LAUREL238 | not matched | 16 |
| CUMBERLAND | Cumberland, MD | 16 |
| WSNG236Z14 | not matched | 14 |
| WSHNGTNZN6 | not matched | 13 |
| LXTNPKGRML | not matched | 12 |
| MYERSVILLE | Myersville, MD | 11 |
| WSNGTNZN16 | not matched | 11 |
| WSNGTNZN12 | not matched | 10 |
| DAMASCS236 | not matched | 9 |
| HUGHESVL | not matched | 9 |
| LA PLATA | La Plata, MD | 8 |
Top 25 of 63 rate centers.
How full is area code 240?
An area code has 800 possible central office codes that start with 2 through 9, a few of which are reserved (such as N11 service codes and 555). 785 are assigned in 240, 98% of 800. 132 were assigned in 2020 or later.
| Decade assigned | Exchanges | Share |
|---|---|---|
| 2000s | 132 | 30% |
| 2010s | 179 | 40% |
| 2020s | 132 | 30% |
Assignment dates as recorded in NANPA's utilized code file; codes without a recorded date are excluded.
A local 240 number on Callata
For $99 a month, Callata puts a team of up to 5 on one plan ($20 for each person after that): up to 3 local numbers, unlimited inbound calls, a pooled allowance of 1,500 outbound US and Canada minutes per user, browser and cell calling, voicemail transcription with urgency triage, recorded calls with AI summaries and business-hours routing, with E911 on every number.
If you already have a number in area code 240, porting it to Callata is free. Texting from a local number requires a one-time carrier registration (10DLC, $49), and the numbers available in any area code depend on carrier inventory when you choose them.
Optional AI agents (receptionist, sales, support or scheduler) can answer calls after hours or when nobody picks up, take messages, text, email and transfer to your team. They are billed from prepaid AI minutes at $0.25 per minute, identify themselves as AI, and may only place outbound calls to people who consented, between 8am and 9pm.
Frequently asked questions
Where is area code 240?
240 is a geographic area code in Maryland. Places with the most assigned exchanges include Frederick, Gaithersburg, Hagerstown, and Leonardtown.
What time zone is area code 240 in?
NANPA lists 240 in the Eastern time zone.
When did area code 240 go into service?
NANPA records an in-service date of June 1, 1997. The code was assigned on June 21, 1996.
Is 240 an overlay area code?
Yes. It shares its territory with 227 and 301.
Can my business get a 240 phone number?
Callata includes up to 3 local numbers on its $99/month plan (5 users included). Which 240 numbers are open depends on carrier inventory when you choose, and you can port an existing number for free.