| Area Code | State, etc. | Main City | Country | Overlay Complex | Time Zone |
|---|---|---|---|---|---|
| 301 | Maryland | Germantown | USA | 301/240/227 | E |
| 302 | Delaware | Wilmington | USA | E | |
| 303 | Colorado | Denver | USA | 303/720/983 | M |
| 304 | West Virginia | Charleston | USA | 304/681 | E |
| 305 | Florida | Miami | USA | 305/786/645 | E |
| 306 | Saskatchewan | Saskatoon | Canada | 306/639/474 | CST |
| 307 | Wyoming | Cheyenne | USA | M | |
| 308 | Nebraska | Grand Island | USA | C,M | |
| 309 | Illinois | Peoria | USA | 309/861 | C |
| 310 | California | Torrance | USA | 310/424 | P |
| 312 | Illinois | Chicago Downtown | USA | 312/872 | C |
| 313 | Michigan | Detroit | USA | E | |
| 314 | Missouri | St Louis | USA | 314/557 | C |
| 315 | New York | Syracuse | USA | 315/680 | E |
| 316 | Kansas | Wichita | USA | C | |
| 317 | Indiana | Indianapolis | USA | 317/463 | E |
| 318 | Louisiana | Shreveport | USA | C | |
| 319 | Iowa | Cedar Rapids | USA | C | |
| 320 | Minnesota | St Cloud | USA | C | |
| 321 | Florida | Orlando | USA | 407/321/689,321 | E |
| 321 | Florida | Palm Bay | USA | E | |
| 323 | California | Los Angeles | USA | 323/213 | P |
| 324 | Florida | Jacksonville | USA | 904/324 | E |
| 325 | Texas | Abilene | USA | C | |
| 326 | Ohio | Dayton | USA | 937/326 | E |
| 327 | Arkansas | Jonesboro | USA | 870/327 | C |
| 329 | New York | New City | USA | 845/329 | E |
| 330 | Ohio | Akron | USA | 330/234 | E |
| 331 | Illinois | Aurora | USA | 630/331 | C |
| 332 | New York | NYC Manhattan | USA | 212/646/917/332 | E |
| 334 | Alabama | Montgomery | USA | C | |
| 336 | North Carolina | Greensboro | USA | 336/743 | E |
| 337 | Louisiana | Lafayette | USA | C | |
| 339 | Massachusetts | Lynn | USA | 781/339 | E |
| 340 | US Virgin Islands | Charlotte Amalie | US Virgin Islands | AST | |
| 341 | California | Oakland | USA | 510/341 | P |
| 343 | Ontario | Ottawa | Canada | 613/343/753 | E |
| 345 | Cayman Islands | George Town | Cayman Islands | EST | |
| 346 | Texas | Houston | USA | 713/281/832/346 | C |
| 347 | New York | New York | USA | 718/347/917/929 | E |
| 350 | California | Stockton | USA | 209/350 | P |
| 351 | Massachusetts | Lowell | USA | 978/351 | E |
| 352 | Florida | Gainesville | USA | E | |
| 353 | Wisconsin | Madison | USA | 608/353 | C |
| 354 | Quebec | Laval | Canada | 450/579/354 | E |
| 360 | Washington | Vancouver | USA | 360/564 | P |
| 361 | Texas | Corpus Christi | USA | C | |
| 363 | New York | Hempstead | USA | 516/363 | E |
| 364 | Kentucky | Bowling Green | USA | 270/364 | E,C |
| 365 | Ontario | Mississauga | Canada | 905/289/365/742 | E |
| 367 | Quebec | Quebec City | Canada | 418/581/367 | E |
| 368 | Alberta | Calgary | Canada | 403/587/825/368, 780/587/825/368 | M |
| 369 | California | Santa Rosa | USA | 707/369 | P |
| 380 | Ohio | Columbus | USA | 614/380 | E |
| 382 | Ontario | London | Canada | 519/226/548/382 | E |
| 385 | Utah | Salt Lake City | USA | 801/385 | M |
| 386 | Florida | Deltona | USA | E |