Area Code 240 Maryland - Exchanges, Map and Location
Area Code 240, Maryland Cities, Neighborhoods and Local Features
Cities in Areacode 240 Maryland
- Aspen Hill
- North Bethesda
- Bowie
- Chillum
- Clinton
- College Park
- Cumberland
- Fairland
- Fort Washington
- Frederick
- Gaithersburg
- Germantown
- Greenbelt
- Hagerstown
- Landover
- Montgomery Village
- North Bethesda
- South Laurel
- North Potomac
- Olney
- Potomac
- Rockville
- Silver Spring
- South Laurel
- Saint Charles
- Suitland
- Waldorf
- White Oak
| Prefix | Usage | Primary City | Carrier |
|---|---|---|---|
| 240-252- | Landline | Gaithersburg | Level 3 Communications |
| 240-264- | Landline | Beltsville | Verizon Maryland |
| 240-481- | Wireless | Silver Spring | Omnipoint Communications Cap Operations |
| 240-275- | Landline | Grantsville | Core Communications |
| 240-218- | Landline | Nanjemoy | Peerless Network Of The District Of Columbia, Dc |
| 240-495- | Wireless | Mount Rainier | Cellco Partnership DBA Verizon Wireless |
| 240-346- | Wireless | Waldorf | Sprint Spectrum L.p. |
| 240-556- | Landline | Glenn Dale | Paetec Communications |
| 240-567- | Landline | Rockville | Verizon Maryland |
| 240-545- | Landline | Upper Marlboro | Us Lec Of Maryland |
| 240-387- | Landline | Chevy Chase | Cavalier East LLC |
| 240-553- | Landline | Mount Rainier | Allegiance Telecom |
| 240-583- | Landline | Beltsville | Verizon Maryland |
| 240-786- | Landline | Laurel | Broadwing Communications. LLC |
| 240-770- | Landline | Oxon Hill | Comcast Phone Of Northern Maryland |
| 240-605- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-419- | Wireless | Waldorf | Cellco Partnership DBA Verizon Wireless |
| 240-559- | Landline | Sandy Spring | Allegiance Telecom |
| 240-593- | Wireless | Laurel | Omnipoint Communications Cap Operations |
| 240-467- | Landline | Oxon Hill | Comcast Phone Of Northern Maryland |
| 240-454- | Wireless | Gaithersburg | Paetec Communications |
| 240-667- | Landline | Mount Rainier | Global Crossing Local Services-md |
| 240-787- | Landline | Brandywine | Broadwing Communications. LLC |
| 240-373- | Landline | Odenton | Verizon Maryland |
| 240-292- | Landline | Kensington | Verizon Maryland |
| 240-994- | Wireless | Rockville | Cellco Partnership DBA Verizon Wireless |
| 240-844- | Landline | Ridge | Xo Maryland |
| 240-459- | Wireless | Laurel | Cellco Partnership DBA Verizon Wireless |
| 240-510- | Landline | Upper Marlboro | Xo Maryland |
| 240-462- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-480- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-536- | Landline | Sandy Spring | Peerless Network Of Maryland |
| 240-929- | Landline | Mount Rainier | Cavalier East LLC |
| 240-614- | Wireless | Rockville | Metro PCS |
| 240-260- | Landline | Mount Rainier | Allegiance Telecom |
| 240-305- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-578- | Wireless | Frederick | Cellco Partnership DBA Verizon Wireless |
| 240-473- | Landline | College Park | Cavalier Telephone Mid-atlantic |
| 240-613- | Landline | Hyattsville | Us Lec Of Maryland |
| 240-398- | Wireless | Cabin John | Sprint Spectrum L.p. |
| 240-516- | Landline | Silver Spring | Us Lec Of Maryland |
| 240-362- | Landline | Cumberland | Verizon Maryland |
| 240-359- | Landline | Indian Head | Peerless Network Of Maryland |
| 240-523- | Landline | La Plata | Xo Maryland |
| 240-652- | Landline | Mechanicsville | Xo Maryland |
| 240-888- | Wireless | Rockville | New Cingular Wireless PCS - DC |
| 240-498- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-253- | Landline | Mount Rainier | Global Crossing Local Services-md |
| 240-440- | Wireless | Frederick | Leap Wireless Intl DBA Cricket Comm |
| 240-716- | Wireless | Mount Rainier | Omnipoint Communications Cap Operations |
| 240-778- | Landline | Chevy Chase | Xo Maryland |
| 240-718- | Landline | Callaway | Xo Maryland |
| 240-348- | Landline | Oxon Hill | Level 3 Communications |
| 240-684- | Landline | Greenbelt | Verizon Maryland |
| 240-539- | Landline | Mount Rainier | Peerless Network Of Maryland |
| 240-379- | Landline | Frederick | Verizon Maryland |
| 240-782- | Landline | Damascus | Global Crossing Local Services-md |
| 240-316- | Wireless | Chevy Chase | Sprint Spectrum L.p. |
| 240-479- | Wireless | Oxon Hill | Cellco Partnership DBA Verizon Wireless |
| 240-229- | Landline | Waldorf | Broadwing Communications. LLC |
| 240-764- | Landline | Chevy Chase | Xo Maryland |
| 240-354- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-204- | Wireless | Bethesda | Cellco Partnership DBA Verizon Wireless |
| 240-307- | Landline | Emmitsburg | AT&T Local |
| 240-503- | Landline | Newburg | Peerless Network Of Maryland |
| 240-715- | Landline | Rockville | Global Crossing Local Services-md |
| 240-615- | Wireless | Hyattsville | Metro PCS |
| 240-727- | Wireless | Cumberland | New Cingular Wireless PCS - DC |
| 240-470- | Wireless | Laurel | Cellco Partnership DBA Verizon Wireless |
| 240-794- | Landline | Callaway | Broadwing Communications. LLC |
| 240-793- | Wireless | Gaithersburg | Sprint Spectrum L.p. |
| 240-788- | Landline | Oxon Hill | Broadwing Communications. LLC |
| 240-258- | Landline | Ridge | Teleport Communications America - DC |
| 240-450- | Landline | Silver Spring | Cavalier Telephone Mid-atlantic |
| 240-461- | Wireless | Silver Spring | New Cingular Wireless PCS - DC |
| 240-330- | Wireless | Cabin John | Sprint Spectrum L.p. |
| 240-645- | Landline | Chevy Chase | Xo Maryland |
| 240-310- | Wireless | Hagerstown | Uscoc Of Cumberland DBA United States Cel Md |
| 240-270- | Wireless | Waldorf | Cellco Partnership DBA Verizon Wireless |
| 240-897- | Landline | Mount Rainier | Broadwing Communications. LLC |
| 240-541- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-284- | Landline | Frostburg | Level 3 Communications |
| 240-458- | Wireless | Waldorf | Cellco Partnership DBA Verizon Wireless |
| 240-453- | Landline | Rockville | Verizon Maryland |
| 240-220- | Landline | Poolesville | Peerless Network Of Maryland |
| 240-832- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-691- | Landline | Mount Rainier | Global Crossing Local Services-md |
| 240-551- | Wireless | Rockville | Leap Wireless Intl DBA Cricket Comm |
| 240-670- | Landline | Mount Rainier | Local Access LLC |
| 240-507- | Wireless | Cabin John | Cellco Partnership DBA Verizon Wireless |
| 240-632- | Landline | Gaithersburg | Verizon Maryland |
| 240-358- | Landline | Damascus | Peerless Network Of Maryland |
| 240-216- | Wireless | Waldorf | Sprint Spectrum L.p. |
| 240-468- | Wireless | Mount Rainier | Sprint Spectrum L.p. |
| 240-376- | Landline | Hughesville | Peerless Network Of Maryland |
| 240-713- | Landline | Laurel | Peerless Network Of Maryland |
| 240-646- | Landline | Laurel | Cavalier East LLC |
| 240-734- | Landline | Hagerstown | Bandwidth.com Clec |
| 240-432- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-224- | Wireless | Gaithersburg | Cellco Partnership DBA Verizon Wireless |
| 240-441- | Wireless | Oxon Hill | Omnipoint Communications Cap Operations |
| 240-743- | Landline | Oxon Hill | Local Access LLC |
| 240-298- | Wireless | Leonardtown | Cellco Partnership DBA Verizon Wireless |
| 240-720- | Landline | Gaithersburg | Global Crossing Local Services-md |
| 240-483- | Landline | Oxon Hill | Comcast Phone Of Northern Maryland |
| 240-228- | Landline | Laurel | Verizon Maryland |
| 240-433- | Landline | Silver Spring | Cavalier Telephone Mid-atlantic |
| 240-257- | Landline | Nanjemoy | Teleport Communications America - DC |
| 240-397- | Wireless | Frederick | Cellco Partnership DBA Verizon Wireless |
| 240-707- | Wireless | Hagerstown | New Cingular Wireless PCS - DC |
| 240-212- | Landline | Oakland | Core Communications |
| 240-585- | Wireless | Waldorf | Cellco Partnership DBA Verizon Wireless |
| 240-780- | Landline | Gaithersburg | Broadwing Communications. LLC |
| 240-704- | Wireless | Mount Rainier | Leap Wireless Intl DBA Cricket Comm |
| 240-244- | Landline | Mount Rainier | Starpower Communications |
| 240-899- | Wireless | Bethesda | Omnipoint Communications Cap Operations |
| 240-331- | Landline | Mount Rainier | Peerless Network Of Maryland |
| 240-694- | Landline | Rockville | Verizon Maryland |
| 240-300- | Wireless | Waldorf | Cellco Partnership DBA Verizon Wireless |
| 240-487- | Landline | Hyattsville | Us Lec Of Maryland |
| 240-497- | Landline | Chevy Chase | Verizon Maryland |
| 240-238- | Landline | Rockville | Paetec Communications |
| 240-347- | Landline | Hagerstown | Bandwidth.com Clec |
| 240-208- | Landline | La Plata | Peerless Network Of The District Of Columbia, Dc |
| 240-408- | Wireless | Rockville | Leap Wireless Intl DBA Cricket Comm |
| 240-708- | Wireless | Columbia | Level 3 Communications |
| 240-364- | Landline | Gaithersburg | Cavalier East LLC |
| 240-676- | Wireless | Silver Spring | Cellco Partnership DBA Verizon Wireless |
| 240-705- | Wireless | Chevy Chase | Leap Wireless Intl DBA Cricket Comm |
| 240-344- | Wireless | Frederick | New Cingular Wireless PCS - DC |
| 240-402- | Landline | College Park | Mci Worldcom Communications |
| 240-838- | Wireless | Oxon Hill | Omnipoint Communications Cap Operations |
| 240-222- | Landline | Waldorf | Cavalier Telephone Mid-atlantic |
| 240-303- | Landline | Clinton | Cavalier Telephone Mid-atlantic |
| 240-841- | Landline | Laurel | Allegiance Telecom |
| 240-234- | Wireless | Mount Rainier | Cellco Partnership DBA Verizon Wireless |
| 240-416- | Wireless | Waldorf | New Cingular Wireless PCS - DC |
| 240-800- | Landline | Chevy Chase | Core Communications |
| 240-504- | Wireless | Silver Spring | Sprint Spectrum L.p. |
| 240-425- | Landline | Cabin John | Dslnet Communications Va |
| 240-833- | Landline | Chevy Chase | Xo Maryland |
| 240-672- | Landline | Rockville | Cellco Partnership DBA Verizon Wireless |
| 240-501- | Wireless | Silver Spring | Sprint Spectrum L.p. |
| 240-640- | Wireless | Waldorf | Leap Wireless Intl DBA Cricket Comm |
| 240-319- | Wireless | Columbia | Cellco Partnership DBA Verizon Wireless |
| 240-773- | Landline | Rockville | Verizon Maryland |
| 240-883- | Landline | Sandy Spring | Broadwing Communications. LLC |
| 240-446- | Wireless | Frederick | Cellco Partnership DBA Verizon Wireless |
| 240-365- | Landline | Damascus | Baltimore-washington Telephone (bwt) |
| 240-772- | Wireless | Frederick | Cellco Partnership DBA Verizon Wireless |
| 240-604- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-912- | Landline | Gaithersburg | Us Lec Of Maryland |
| 240-631- | Landline | Gaithersburg | Verizon Maryland |
| 240-384- | Landline | Callaway | Peerless Network Of Maryland |
| 240-476- | Wireless | Silver Spring | Omnipoint Communications Cap Operations |
| 240-250- | Landline | Brandywine | Peerless Network Of Maryland |
| 240-535- | Wireless | Silver Spring | New Cingular Wireless PCS - DC |
| 240-426- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-779- | Landline | Sandy Spring | Cavalier East LLC |
| 240-363- | Landline | Kensington | Global Naps South |
| 240-550- | Wireless | Rockville | Leap Wireless Intl DBA Cricket Comm |
| 240-217- | Wireless | Hagerstown | Omnipoint Communications Cap Operations |
| 240-621- | Landline | Kensington | Mci Worldcom Communications |
| 240-530- | Landline | Waldorf | Local Access LLC |
| 240-265- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-353- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-668- | Landline | Damascus | Starpower Communications |
| 240-313- | Landline | Hagerstown | Verizon Maryland |
| 240-606- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-582- | Landline | Hyattsville | Verizon Maryland |
| 240-328- | Landline | Rockville | Verizon Maryland |
| 240-595- | Wireless | Chevy Chase | Cellco Partnership DBA Verizon Wireless |
| 240-424- | Wireless | Mount Rainier | Sprint Spectrum L.p. |
| 240-375- | Wireless | Capitol Heights | Sprint Spectrum L.p. |
| 240-895- | Landline | Lexington Park | Verizon Maryland |
| 240-466- | Wireless | Mechanicsville | New Cingular Wireless PCS - DC |
| 240-477- | Landline | Gaithersburg | Lightwave Communications |
| 240-438- | Wireless | Silver Spring | Sprint Spectrum L.p. |
| 240-737- | Landline | Mount Rainier | Cavalier East LLC |
| 240-380- | Wireless | Cabin John | Cellco Partnership DBA Verizon Wireless |
| 240-447- | Wireless | Rockville | New Cingular Wireless PCS - DC |
| 240-351- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-493- | Landline | Oxon Hill | Us Lec Of Maryland |
| 240-568- | Landline | Laurel | Verizon Maryland |
| 240-296- | Landline | Hyattsville | Cavalier Telephone Mid-atlantic |
| 240-608- | Wireless | Frederick | 365 Wireless |
| 240-784- | Wireless | Myersville | Omnipoint Communications Cap Operations |
| 240-766- | Landline | Chevy Chase | Xo Maryland |
| 240-361- | Landline | Gaithersburg | Cavalier Telephone Mid-atlantic |
| 240-269- | Landline | Mount Rainier | Peerless Network Of Maryland |
| 240-687- | Wireless | Silver Spring | Cellco Partnership DBA Verizon Wireless |
| 240-205- | Wireless | Cabin John | New Cingular Wireless PCS - DC |
| 240-654- | Wireless | Gaithersburg | New Cingular Wireless PCS - DC |
| 240-295- | Landline | Laurel | Cavalier Telephone Mid-atlantic |
| 240-626- | Wireless | Frederick | Sprint Spectrum L.p. |
| 240-420- | Landline | Hagerstown | Verizon Maryland |
| 240-281- | Wireless | Bethesda | New Cingular Wireless PCS - DC |
| 240-846- | Landline | Clinton | Xo Maryland |
| 240-616- | Landline | College Park | Mci Worldcom Communications |
| 240-405- | Landline | Frederick | Us Lec Of Maryland |
| 240-243- | Landline | Gaithersburg | Allegiance Telecom |
| 240-381- | Wireless | Silver Spring | New Cingular Wireless PCS - DC |
| 240-542- | Landline | College Park | Us Lec Of Maryland |
| 240-237- | Landline | Callaway | Teleport Communications America - DC |
| 240-246- | Landline | Gaithersburg | Starpower Communications |
| 240-747- | Landline | Mount Rainier | Cavalier East LLC |
| 240-287- | Landline | Hancock | Core Communications |
| 240-485- | Landline | Cabin John | Us Lec Of Maryland |
| 240-755- | Landline | Laurel | Comcast Phone Of Northern Maryland |
| 240-882- | Wireless | Capitol Heights | Sprint Spectrum L.p. |
| 240-554- | Landline | Laurel | Allegiance Telecom |
| 240-669- | Landline | Kensington | Comcast Phone Of Northern Maryland |
| 240-254- | Landline | Hughesville | Teleport Communications America - DC |
| 240-439- | Wireless | Frederick | Cellco Partnership DBA Verizon Wireless |
| 240-526- | Landline | Leonardtown | Peerless Network Of Maryland |
| 240-434- | Landline | Leonardtown | Broadwing Communications. LLC |
| 240-675- | Wireless | Myersville | New Cingular Wireless PCS - DC |
| 240-612- | Landline | Mount Rainier | Tw Telecom Of Maryland LLC |
| 240-650- | Landline | Cabin John | Broadvox-clec - DC |
| 240-209- | Landline | Indian Head | Peerless Network Of The District Of Columbia, Dc |
| 240-548- | Landline | Mount Rainier | Allegiance Telecom |
| 240-337- | Landline | Mount Rainier | Peerless Network Of Maryland |
| 240-818- | Landline | Smithsburg | Verizon Maryland |
| 240-525- | Landline | Upper Marlboro | Peerless Network Of Maryland |
| 240-471- | Landline | Silver Spring | Global Crossing Local Services-md |
| 240-986- | Landline | Nanjemoy | Xo Maryland |
| 240-643- | Wireless | Silver Spring | Omnipoint Communications Cap Operations |
| 240-607- | Landline | Waldorf | Global Crossing Local Services-md |
| 240-423- | Wireless | Silver Spring | Omnipoint Communications Cap Operations |
| 240-324- | Landline | Clarksville | Ymax Communications Corp. |
| 240-404- | Landline | Gaithersburg | Xo Maryland |
| 240-599- | Landline | Rockville | Broadwing Communications. LLC |
| 240-538- | Landline | Leonardtown | Xo Maryland |
| 240-368- | Landline | Waldorf | Peerless Network Of Maryland |
| 240-533- | Landline | Mount Rainier | Teleport Communications America - DC |
| 240-277- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-699- | Landline | Adamstown | Verizon Maryland |
| 240-696- | Landline | Hyattsville | Level 3 Communications |
| 240-352- | Landline | La Plata | Peerless Network Of Maryland |
| 240-464- | Landline | Chevy Chase | Sprint Spectrum L.p. |
| 240-286- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-213- | Landline | Waldorf | Peerless Network Of The District Of Columbia, Dc |
| 240-508- | Wireless | Capitol Heights | Sprint Spectrum L.p. |
| 240-436- | Landline | Ijamsville | Telcove Operations |
| 240-597- | Landline | Gaithersburg | Peerless Network Of Maryland |
| 240-519- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-367- | Wireless | Frederick | Sprint Spectrum L.p. |
| 240-522- | Wireless | Cumberland | Sprint Spectrum L.p. |
| 240-486- | Wireless | Glenn Dale | Omnipoint Communications Cap Operations |
| 240-374- | Landline | Laurel | Global Crossing Local Services-md |
| 240-803- | Wireless | Cumberland | New Cingular Wireless PCS - DC |
| 240-266- | Landline | Mount Rainier | Peerless Network Of Maryland |
| 240-320- | Landline | Waldorf | Cavalier East LLC |
| 240-644- | Landline | Chevy Chase | Xo Maryland |
| 240-790- | Landline | Mount Rainier | Broadwing Communications. LLC |
| 240-776- | Landline | La Plata | Broadwing Communications. LLC |
| 240-210- | Wireless | Waldorf | New Cingular Wireless PCS - DC |
| 240-500- | Landline | Hagerstown | Us Lec Of Maryland |
| 240-565- | Wireless | Laurel | Omnipoint Communications Cap Operations |
| 240-215- | Landline | Frederick | Telcove Operations |
| 240-731- | Wireless | Rockville | New Cingular Wireless PCS - DC |
| 240-581- | Landline | Laurel | Paetec Communications - DC |
| 240-826- | Landline | Rockville | Verizon Maryland |
| 240-489- | Landline | Poolesville | Xo Maryland |
| 240-201- | Landline | Ridge | Peerless Network Of The District Of Columbia, Dc |
| 240-385- | Landline | Myersville | Verizon Maryland |
| 240-294- | Landline | Laurel | Xo Maryland |
| 240-401- | Wireless | Rockville | New Cingular Wireless PCS - DC |
| 240-812- | Landline | Poolesville | Global Crossing Local Services-md |
| 240-843- | Landline | College Park | Allegiance Telecom |
| 240-272- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-414- | Landline | Mount Rainier | Peerless Network Of Maryland |
| 240-417- | Wireless | Capitol Heights | Sprint Spectrum L.p. |
| 240-394- | Wireless | Mount Airy | New Cingular Wireless PCS - DC |
| 240-561- | Wireless | Leonardtown | Cellco Partnership DBA Verizon Wireless |
| 240-577- | Wireless | Leonardtown | Cellco Partnership DBA Verizon Wireless |
| 240-575- | Landline | Frederick | Level 3 Communications |
| 240-206- | Landline | Glenn Dale | Xo Maryland |
| 240-518- | Wireless | Waldorf | Sprint Spectrum L.p. |
| 240-671- | Wireless | Mount Rainier | Sprint Spectrum L.p. |
| 240-465- | Landline | Mount Rainier | Peerless Network Of Maryland |
| 240-435- | Wireless | Waldorf | Cellco Partnership DBA Verizon Wireless |
| 240-456- | Landline | Laurel | Verizon Maryland |
| 240-903- | Landline | Indian Head | Comcast Phone Of Northern Maryland |
| 240-865- | Landline | Baltimore | Level 3 Communications |
| 240-431- | Wireless | Tall Timbers | Sprint Spectrum L.p. |
| 240-304- | Wireless | Mount Rainier | Sprint Spectrum L.p. |
| 240-457- | Wireless | Frederick | Cellco Partnership DBA Verizon Wireless |
| 240-979- | Landline | Cumberland | Level 3 Communications |
| 240-993- | Landline | Indian Head | Xo Maryland |
| 240-231- | Landline | Hagerstown | Core Communications |
| 240-415- | Landline | Frederick | Ymax Communications Corp. |
| 240-207- | Landline | Damascus | Cavalier East LLC |
| 240-444- | Wireless | Laurel | Cellco Partnership DBA Verizon Wireless |
| 240-268- | Landline | Rockville | Allegiance Telecom |
| 240-712- | Wireless | Columbia | Cellco Partnership DBA Verizon Wireless |
| 240-357- | Wireless | Frederick | Cellco Partnership DBA Verizon Wireless |
| 240-263- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-372- | Wireless | Gaithersburg | Sprint Spectrum L.p. |
| 240-309- | Wireless | Leonardtown | Cellco Partnership DBA Verizon Wireless |
| 240-449- | Wireless | Gaithersburg | New Cingular Wireless PCS - DC |
| 240-706- | Wireless | Chevy Chase | Leap Wireless Intl DBA Cricket Comm |
| 240-528- | Landline | Hughesville | Broadwing Communications. LLC |
| 240-988- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-317- | Landline | Callaway | Starpower Communications |
| 240-308- | Wireless | Damascus | New Cingular Wireless PCS - DC |
| 240-997- | Wireless | Silver Spring | Cellco Partnership DBA Verizon Wireless |
| 240-271- | Wireless | Bethesda | New Cingular Wireless PCS - DC |
| 240-620- | Landline | Rockville | Mci Worldcom Communications |
| 240-543- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-406- | Wireless | Rockville | Leap Wireless Intl DBA Cricket Comm |
| 240-242- | Landline | Kensington | Starpower Communications |
| 240-949- | Landline | Mount Rainier | Cavalier East LLC |
| 240-804- | Landline | Newburg | Xo Maryland |
| 240-880- | Landline | Chevy Chase | Broadwing Communications. LLC |
| 240-762- | Wireless | Mount Rainier | Cellco Partnership DBA Verizon Wireless |
| 240-236- | Landline | Frederick | Verizon Maryland |
| 240-318- | Landline | Clinton | Verizon Maryland |
| 240-428- | Landline | Rockville | Bandwidth.com Clec |
| 240-529- | Landline | Frederick | Verizon Maryland |
| 240-494- | Landline | Mount Rainier | Cavalier East LLC |
| 240-371- | Landline | Mount Rainier | Peerless Network Of Maryland |
| 240-617- | Unknown | Shentel Communications | |
| 240-515- | Wireless | Bethesda | New Cingular Wireless PCS - DC |
| 240-892- | Landline | Upper Marlboro | Broadwing Communications. LLC |
| 240-512- | Landline | College Park | Core Communications |
| 240-392- | Landline | Oxon Hill | Starpower Communications |
| 240-442- | Landline | Oakland | Verizon Maryland |
| 240-278- | Wireless | Laurel | Cellco Partnership DBA Verizon Wireless |
| 240-339- | Landline | Upper Marlboro | Cavalier East LLC |
| 240-802- | Wireless | Bethesda | 365 Wireless |
| 240-695- | Landline | Temple Hills | Verizon Maryland |
| 240-864- | Landline | Rockville | Cavalier East LLC |
| 240-396- | Landline | Mount Rainier | Global Crossing Local Services-md |
| 240-325- | Landline | Damascus | Core Communications |
| 240-767- | Landline | Capitol Heights | Cavalier East LLC |
| 240-288- | Landline | Thurmont | Comcast Phone Of Northern Maryland |
| 240-247- | Landline | Mount Rainier | Allegiance Telecom |
| 240-662- | Landline | Silver Spring | Verizon Maryland |
| 240-403- | Landline | Rockville | Cavalier Telephone Mid-atlantic |
| 240-488- | Landline | Oakland | Shentel Communications |
| 240-383- | Wireless | Chevy Chase | New Cingular Wireless PCS - DC |
| 240-750- | Wireless | Gaithersburg | New Cingular Wireless PCS - DC |
| 240-674- | Wireless | Frederick | Sprint Spectrum L.p. |
| 240-395- | Landline | Bethesda | Cavalier Telephone Mid-atlantic |
| 240-355- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-315- | Landline | Frederick | Verizon Maryland |
| 240-297- | Landline | College Park | Level 3 Communications |
| 240-490- | Wireless | Middletown | Omnipoint Communications Cap Operations |
| 240-366- | Landline | Williamsport | AT&T Local |
| 240-722- | Landline | Sandy Spring | Global Crossing Local Services-md |
| 240-306- | Landline | Gaithersburg | Allegiance Telecom |
| 240-514- | Landline | Cabin John | Us Lec Of Maryland |
| 240-686- | Landline | Gaithersburg | Verizon Maryland |
| 240-532- | Wireless | Oxon Hill | Cellco Partnership DBA Verizon Wireless |
| 240-651- | Wireless | Frederick | Halo Wireless Services |
| 240-393- | Wireless | Cabin John | Cellco Partnership DBA Verizon Wireless |
| 240-332- | Landline | Newburg | Peerless Network Of Maryland |
| 240-753- | Landline | Rockville | Telcove Operations |
| 240-413- | Wireless | Hyattsville | Omnipoint Communications Cap Operations |
| 240-682- | Landline | Waldorf | Starpower Communications |
| 240-427- | Landline | Waldorf | Xo Maryland |
| 240-754- | Landline | Waldorf | Level 3 Communications |
| 240-321- | Wireless | Oakland | Uscoc Of Cumberland DBA United States Cel Md |
| 240-475- | Wireless | Silver Spring | New Cingular Wireless PCS - DC |
| 240-725- | Landline | Lexington Park | Verizon Maryland |
| 240-280- | Landline | Laurel | Comcast Phone Of Northern Maryland |
| 240-625- | Wireless | Hagerstown | Sprint Spectrum L.p. |
| 240-492- | Landline | Capitol Heights | Us Lec Of Maryland |
| 240-845- | Landline | Chevy Chase | Xo Maryland |
| 240-386- | Landline | Gaithersburg | Verizon Maryland |
| 240-279- | Landline | Waldorf | Core Communications |
| 240-314- | Landline | Rockville | Verizon Maryland |
| 240-964- | Landline | Cumberland | Verizon Maryland |
| 240-274- | Wireless | Bethesda | New Cingular Wireless PCS - DC |
| 240-573- | Landline | Upper Marlboro | Global Crossing Local Services-md |
| 240-777- | Landline | Rockville | Verizon Maryland |
| 240-624- | Landline | Greenbelt | Verizon Maryland |
| 240-290- | Landline | Mount Rainier | Allegiance Telecom |
| 240-469- | Wireless | Hagerstown | Sprint Spectrum L.p. |
| 240-898- | Landline | Mount Rainier | Broadwing Communications. LLC |
| 240-560- | Landline | Chevy Chase | Xo Maryland |
| 240-378- | Landline | Cumberland | Core Communications |
| 240-203- | Landline | Hagerstown | Bandwidth.com |
| 240-455- | Landline | Oxon Hill | Paetec Communications |
| 240-409- | Wireless | Frederick | New Cingular Wireless PCS - DC |
| 240-340- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-491- | Landline | Mount Rainier | Global Crossing Local Services-md |
| 240-389- | Landline | Sandy Spring | Atx Telecommunications Services, Ltd |
| 240-293- | Landline | Mount Rainier | Starpower Communications |
| 240-765- | Landline | Chevy Chase | Xo Maryland |
| 240-920- | Landline | Cumberland | Level 3 Communications |
| 240-221- | Landline | Rockville | Verizon Maryland |
| 240-580- | Wireless | Cumberland | Sprint Spectrum L.p. |
| 240-343- | Wireless | Hancock | Cellco Partnership DBA Verizon Wireless |
| 240-499- | Landline | Cabin John | Us Lec Of Maryland |
| 240-630- | Landline | Mount Rainier | Bandwidth.com Clec |
| 240-350- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-437- | Landline | Sandy Spring | Xo Maryland |
| 240-723- | Landline | Silver Spring | Cellco Partnership DBA Verizon Wireless |
| 240-938- | Wireless | Ashton | Omnipoint Communications Cap Operations |
| 240-326- | Landline | Upper Marlboro | Cavalier Telephone Mid-atlantic |
| 240-544- | Landline | Glenn Dale | Us Lec Of Maryland |
| 240-527- | Landline | Hagerstown | Verizon Maryland |
| 240-506- | Wireless | Rockville | New Cingular Wireless PCS - DC |
| 240-502- | Wireless | Silver Spring | Sprint Spectrum L.p. |
| 240-333- | Landline | Mount Rainier | Cavalier East LLC |
| 240-976- | Unknown | Baltimore-washington Telephone (bwt) | |
| 240-400- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-214- | Landline | Mechanicsville | Peerless Network Of The District Of Columbia, Dc |
| 240-965- | Landline | College Park | Paetec Communications |
| 240-233- | Landline | Newburg | Teleport Communications America - DC |
| 240-520- | Wireless | Hagerstown | Sprint Spectrum L.p. |
| 240-338- | Wireless | Silver Spring | Cellco Partnership DBA Verizon Wireless |
| 240-603- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-839- | Wireless | Silver Spring | Cellco Partnership DBA Verizon Wireless |
| 240-724- | Landline | Mount Rainier | Cavalier East LLC |
| 240-627- | Landline | Mount Rainier | Global Crossing Local Services-md |
| 240-823- | Landline | Brandywine | Xo Maryland |
| 240-837- | Landline | Hughesville | Xo Maryland |
| 240-245- | Landline | Glenn Dale | Starpower Communications |
| 240-745- | Landline | Damascus | Xo Maryland |
| 240-813- | Landline | Gaithersburg | Atx Telecommunications Services, Ltd |
| 240-399- | Landline | Chevy Chase | Xo Maryland |
| 240-390- | Landline | Sandy Spring | Cavalier Telephone Mid-atlantic |
| 240-848- | Wireless | Gaithersburg | Sprint Spectrum L.p. |
| 240-546- | Landline | Clinton | Us Lec Of Maryland |
| 240-407- | Landline | Mount Rainier | Global Crossing Local Services-md |
| 240-391- | Landline | Mount Rainier | Global Crossing Local Services-md |
| 240-341- | Landline | Adamstown | Mci Worldcom Communications |
| 240-336- | Landline | Bethesda | Core Communications |
| 240-349- | Landline | La Plata | Global Crossing Local Services-md |
| 240-558- | Landline | Kensington | Cavalier Telephone Mid-atlantic |
| 240-329- | Landline | Hagerstown | Level 3 Communications |
| 240-282- | Landline | Mechanicsville | Peerless Network Of Maryland |
| 240-478- | Wireless | Cabin John | New Cingular Wireless PCS - DC |
| 240-249- | Landline | Mechanicsville | Teleport Communications America - DC |
| 240-821- | Landline | Silver Spring | Lightwave Communications |
| 240-370- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-629- | Landline | Frederick | Verizon Maryland |
| 240-421- | Wireless | Rockville | Omnipoint Communications Cap Operations |
| 240-901- | Unknown | Centurylink Communications LLC | |
| 240-342- | Landline | Sandy Spring | Starpower Communications |
| 240-893- | Wireless | Silver Spring | New Cingular Wireless PCS - DC |
| 240-683- | Landline | Gaithersburg | Verizon Maryland |
| 240-255- | Landline | Poolesville | Peerless Network Of Maryland |
| 240-334- | Landline | Mount Rainier | Global Crossing Local Services-md |
| 240-369- | Landline | Mount Airy | Core Communications |
| 240-482- | Landline | Cabin John | Us Lec Of Maryland |
| 240-291- | Wireless | Hagerstown | New Cingular Wireless PCS - DC |
| 240-377- | Landline | Indian Head | Global Crossing Local Services-md |
| 240-842- | Landline | Glenn Dale | Allegiance Telecom |
| 240-600- | Wireless | Mount Rainier | Sprint Spectrum L.p. |
| 240-688- | Wireless | Silver Spring | Cellco Partnership DBA Verizon Wireless |
| 240-925- | Wireless | Leonardtown | Cellco Partnership DBA Verizon Wireless |
| 240-863- | Landline | Laurel | Tw Telecom Of Maryland LLC |
| 240-273- | Landline | Mount Rainier | Broadwing Communications. LLC |
| 240-855- | Wireless | Cabin John | Sprint Spectrum L.p. |
| 240-460- | Wireless | Silver Spring | New Cingular Wireless PCS - DC |
| 240-876- | Wireless | Bethesda | Sprint Spectrum L.p. |
| 240-241- | Landline | Chevy Chase | Starpower Communications |
| 240-744- | Landline | Mount Rainier | Broadwing Communications. LLC |
| 240-335- | Landline | Glenn Dale | Cavalier Telephone Mid-atlantic |
| 240-235- | Landline | Bethesda | Paetec Communications |
| 240-430- | Landline | Kensington | Cavalier Telephone Mid-atlantic |
| 240-801- | Wireless | Gaithersburg | Cellco Partnership DBA Verizon Wireless |
| 240-678- | Wireless | Silver Spring | Cellco Partnership DBA Verizon Wireless |
| 240-472- | Wireless | Silver Spring | New Cingular Wireless PCS - DC |
| 240-619- | Landline | Chevy Chase | Mci Worldcom Communications |
| 240-857- | Landline | Mount Rainier | Tw Telecom Of Maryland LLC |
| 240-323- | Landline | Emmitsburg | Core Communications |
| 240-601- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-602- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-232- | Landline | Mount Rainier | Broadwing Communications. LLC |
| 240-509- | Landline | Crofton | Bandwidth.com Clec |
| 240-276- | Landline | Rockville | Verizon Maryland |
| 240-552- | Wireless | Rockville | Leap Wireless Intl DBA Cricket Comm |
| 240-356- | Landline | Frederick | Level 3 Communications |
| 240-513- | Wireless | Hagerstown | Sprint Spectrum L.p. |
| 240-566- | Landline | Frederick | Verizon Maryland |
| 240-505- | Wireless | Silver Spring | Omnipoint Communications Cap Operations |
| 240-868- | Landline | Mount Rainier | Cavalier East LLC |
| 240-452- | Landline | Hagerstown | Lumos Networks Inc. - VA |
| 240-239- | Landline | Leonardtown | Core Communications |
| 240-586- | Landline | Frederick | Verizon Maryland |
| 240-752- | Landline | Bethesda | Telcove Operations |
| 240-701- | Wireless | Silver Spring | Leap Wireless Intl DBA Cricket Comm |
| 240-283- | Landline | Kensington | Paetec Communications |
| 240-327- | Landline | Gaithersburg | Core Communications |
| 240-289- | Landline | Oxon Hill | Cavalier Telephone Mid-atlantic |
| 240-360- | Wireless | Laurel | Omnipoint Communications Cap Operations |
| 240-448- | Wireless | Waldorf | Sprint Spectrum L.p. |
| 240-418- | Wireless | Beltsville | Sprint Spectrum L.p. |
| 240-463- | Wireless | Silver Spring | New Cingular Wireless PCS - DC |
| 240-783- | Wireless | Bethesda | Mte DBA Mte Paging Network |
| 240-524- | Landline | Laurel | Peerless Network Of Maryland |
| 240-429- | Wireless | Silver Spring | Cellco Partnership DBA Verizon Wireless |
| 240-256- | Landline | Leonardtown | Teleport Communications America - DC |
| 240-312- | Landline | Capitol Heights | Cavalier Telephone Mid-atlantic |
| 240-225- | Landline | Frederick | Core Communications |
| 240-200- | Landline | Mount Rainier | Bandwidth.com Clec |
| 240-248- | Landline | Ridge | Peerless Network Of Maryland |
| 240-345- | Landline | Sandy Spring | Level 3 Communications |
| 240-638- | Landline | Mount Rainier | Broadwing Communications. LLC |
| 240-587- | Wireless | Leonardtown | Cellco Partnership DBA Verizon Wireless |
| 240-299- | Wireless | Waldorf | Sprint Spectrum L.p. |
| 240-262- | Wireless | Callaway | Sprint Spectrum L.p. |
| 240-388- | Wireless | Gaithersburg | Sprint Spectrum L.p. |
| 240-751- | Landline | Gaithersburg | Telcove Operations |
| 240-382- | Landline | Hagerstown | Teleport Communications America |
| 240-757- | Landline | Mount Rainier | Peerless Network Of Maryland |
| 240-547- | Landline | Laurel | Level 3 Communications |
| 240-251- | Landline | Highfield | Core Communications |
| 240-230- | Landline | Hughesville | Global Crossing Local Services-md |
| 240-412- | Wireless | Waldorf | Sprint Spectrum L.p. |
| 240-223- | Landline | Mount Rainier | Allegiance Telecom |
| 240-285- | Landline | Frederick | Cellco Partnership DBA Verizon Wireless |
| 240-422- | Wireless | Frederick | Omnipoint Communications Cap Operations |
| 240-685- | Landline | Brandywine | Global Crossing Local Services-md |
| 240-322- | Landline | Mccoole | Core Communications |
| 240-445- | Wireless | Bethesda | Sprint Spectrum L.p. |