| 401 | Rhode Island (all) |
| 402 | Nebraska (Lincoln, Norfolk, Omaha, Superior, Crofton and eastern Nebraska) |
| 403 | Alberta (Calgary, Banff, Red Deer, Medicine Hat, Lethbridge, Brooks and southern Alberta) |
| 404 | Georgia (Atlanta area inside Interstate 285 perimeter, overlay by 678) |
| 405 | Oklahoma (Oklahoma City, Stillwater, Edmond, Norman, Shawnee, Chickasha and central Oklahoma) |
| 406 | Montana (all) |
| 407 | Florida (Orlando, Cocoa Beach, St. Cloud and central eastern Florida, partial overlay with 321) |
| 408 | California (Los Gatos, Milpitas, Sunnyvale, Cupertino and San Jose area) |
| 409 | Texas (Beaumont, Galveston, Port Arthur, Jasper and Southeast Texas) |
| 410 | Maryland (Annapolis, Baltimore, Salisbury and eastern Maryland, overlays with 443) |
| 411 | Directory Services; 1-areacode-555-1212 is also used. |
| 412 | Pennsylvania (Pittsburgh area, McKeesport, Braddock, Duquesne, overlays with 878) |
| 413 | Massachusetts (Pittsfield, Springfield, Holyoke, Greenfield and western Massachusetts) |
| 414 | Wisconsin (Milwaukee and nearby suburbs) |
| 415 | California (San Francisco, Marin County) |
| 416 | Ontario (Toronto; overlays with 647) |
| 417 | Missouri (Joplin, Springfield, West Plains, Lamar, Lebanon and southwestern Missouri) |
| 418 | Quebec (Quebec City, Saguenay, Gaspe Peninsula, Cote-Nord, Chibougamau, St-Georges, overlays with 581) |
| 419 | Ohio (Toledo, Sylvania, Mansfield, Lima, Findlay,Bryan, Sandusky, Bowling Green and northwestern Ohio, overlays with 567) |
| 423 | Tennessee (Two disconnected portions of East Tennessee-Bristol, Johnson City, Kingsport in north; Chattanooga, Cleveland in south), split from 615 |
| 424 | California (West Los Angeles), overlay with area code 310 |
| 425 | Washington (north and east Seattle suburbs including Everett, Bellevue, Redmond, Renton, Kirkland, Bothell, Issaquah, Edmonds, Lynnwood and Mountlake Terrace) |
| 430 | Texas (Northeast Texas, overlays with area code 903) |
| 432 | Texas (West Texas: Big Spring, Midland, Odessa) |
| 434 | Virginia (Lynchburg, Danville, Farmville, South Hill, Charlottesville; southside and south-central Virginia) |
| 435 | Utah (Logan, Park City, St. George, Moab and all of Utah excluding Salt Lake City, Ogden, Provo, Morgan County, Utah, Davis County, Utah, and north central Utah) |
| 438 | Quebec (Montreal area; overlays with 514) |
| 440 | Ohio (Cleveland suburbs, Elyria, Lorain, Oberlin, Wellington and north central Ohio) |
| 441 | Bermuda, split from 809. (all) |
| 442 | California This Area code is scheduled to provide numbering relief to Area code 760 but no date has been assigned for this to go into effect. |
| 443 | Maryland (Annapolis, Baltimore, Salisbury and eastern Maryland, overlays with 410) |
| 445 | Pennsylvania (Philadelphia area, overlays with 215 and 267) Area code 445 is listed in the North American Numbering Plan web site and other sites (see the Pennsylvania Public Utility Commission web site) as no longer assigned for any location. |
| 447 | Illinois |
| 450 | Quebec (central southern Quebec including the city of Laval but excluding Montreal) |
| 456 | Inbound International Calls |
| 464 | Illinois Overlay of Area code 708 |
| 469 | Texas (Dallas area, overlays with 214 and 972) |
| 470 | Georgia (future overlay for metro Atlanta, over 404/678 and 770/678 areas) |
| 473 | Grenada, split from 809. (all) |
| 475 | Connecticut (Bridgeport, New Haven, Waterbury and southwestern Connecticut, overlays with 203). |
| 478 | Georgia (Macon, Warner Robins, Swainsboro, Wadley, Milledgeville, Perry and central Georgia) |
| 479 | Arkansas (Fort Smith, Fayetteville and northwestern Arkansas) |
| 480 | Arizona (Mesa, Chandler, Gilbert, Tempe, Queen Creek, Scottsdale, eastern Phoenix area and eastern Phoenix suburbs only) |
| 484 | Pennsylvania (Reading, Allentown, Chester and southeastern Pennsylvania, overlays with 610 and 835) |
