Area code 303
Encyclopedia
Image:Area_codes_CO.svg|right|Map of Colorado area codes in blue (with border states)
poly 67 8 381 26 380 108 356 107 352 131 343 130 340 107 326 102 320 104 301 104 301 85 282 85 287 77 263 77 259 84 216 79 204 102 182 125 177 144 191 151 199 177 180 203 168 207 166 219 151 219 149 229 167 226 168 238 186 238 196 227 203 228 211 241 199 262 42 247 Area code 970
Area code 970
Area Code 970: ColoradoImage:Area_codes_CO.svg|right|Map of Colorado area codes in blue #poly 67 8 381 26 380 108 356 107 352 131 343 130 340 107 326 102 320 104 301 104 301 85 282 85 287 77 263 77 259 84 216 79 204 102 182 125 177 144 191 151 199 177 180 203 168 207 166 219 151 219 149 229 167...
- poly 216 80 207 100 195 109 199 120 211 125 213 132 221 132 223 142 283 145 302 106 302 86 282 85 286 79 261 78 259 83 Area codes 303 and 720
poly 378 107 356 107 350 133 342 130 342 107 324 100 300 105 283 144 224 141 221 131 212 132 211 126 198 119 195 109 179 125 178 143 193 151 198 178 181 203 165 207 164 218 149 219 149 231 166 227 168 238 186 239 195 226 205 230 211 242 200 261 376 270 Area code 719
Area code 719
Image:Area_codes_CO.svg|right|Map of Colorado area codes in blue poly 67 8 381 26 380 108 356 107 352 131 343 130 340 107 326 102 320 104 301 104 301 85 282 85 287 77 263 77 259 84 216 79 204 102 182 125 177 144 191 151 199 177 180 203 168 207 166 219 151 219 149 229 167 226 168 238 186 238 196...
poly 380 87 427 89 426 168 377 171 Area code 785
Area code 785
Area Code 785 was the result of a split from 913 on July 20 1997. It covers most telephone exchanges in northern Kansas. It stretches from the Colorado state line on the west to the Missouri state line on the east, while excluding the Kansas City Metropolitan Area . The permissive dialing period...
poly 380 26 290 23 290 0 422 0 425 87 380 88 Area code 308
Area code 308
Image:Area_code_NE.png|right|Map of Nebraska area codes in blue poly 50 20 272 25 291 37 298 32 323 30 340 38 353 50 347 36 354 16 346 7 350 1 47 0 Area code 605...
poly 291 24 4 1 291 0 Area code 307
Area code 307
Image:Area_code_WY.png|right|Map of Wyoming showing its area code in blue #poly 83 35 344 34 353 243 75 246 Area Code 307poly 347 139 425 139 420 0 343 0 Area code 605poly 348 139 429 139 420 243 352 243 Area code 308...
poly 42 245 0 243 0 1 66 7 Area code 435
Area code 435
North American area code 435 is a state of Utah telephone area code which covers all of Utah outside the Salt Lake City, Ogden, and Provo metropolitan areas. It split from the 801 area code on September 21, 1997, and includes St. George, Park City, Price, Moab, Logan, and Tooele.-External links:*...
poly 38 292 0 293 0 242 42 247 Area code 928
Area code 928
North American area code 928 is a telephone area code in the state of Arizona that was created in a split from area Code 520 on June 23, 2001, due mainly to population gains in Tucson, Yuma and Flagstaff. 928 covers northern, eastern, and western portions of Arizona...
poly 119 253 107 262 104 294 327 294 330 268 Area code 575
Area code 575
Image:Area codes NM.svg|300px|right|The map indicates the geographical regions in the state of New Mexico, served by area codes 505 and 575poly 48 199 48 36 135 37 143 42 129 47 128 104 142 105 158 116 158 118 148 127 163 136 167 147 189 147 189 140 178 135 192 113 179 111 184 98 189 103 198 88 207...
poly 45 247 41 294 104 294 107 262 119 253 Area code 505
Area code 505
Image:Area codes NM.svg|300px|right|The map indicates the geographical regions in the state of New Mexico, served by area codes 505 and 575poly 48 199 48 36 135 37 143 42 129 47 128 104 142 105 158 116 158 118 148 127 163 136 167 147 189 147 189 140 178 135 192 113 179 111 184 98 189 103 198 88 207...
poly 329 293 425 293 425 271 330 268 Area code 580
Area code 580
Area code 580 serves the state of Oklahoma. It covers the remainder of the state not included in the Oklahoma City or Tulsa areas, including Ada, Lawton, Enid, Ponca City, Altus, Frederick, Weatherford, Guymon, Durant, and Ardmore....
poly 376 170 426 170 427 270 375 270 Area code 620
Area code 620
Area Code 620 was the result of a split from 316 on February 3 2001. It covers most telephone exchanges in southern Kansas. It stretches from the Colorado state line on the west to the Missouri state line on the east, while excluding the Wichita Metropolitan Area . The permissive dialing period for...
desc top-right
Area codes 303 and 720 are telephone
Telephone
The telephone , colloquially referred to as a phone, is a telecommunications device that transmits and receives sounds, usually the human voice. Telephones are a point-to-point communication system whose most basic function is to allow two people separated by large distances to talk to each other...
area codes serving the state of Colorado
Colorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...
. They cover Denver
Denver, Colorado
The City and County of Denver is the capital and the most populous city of the U.S. state of Colorado. Denver is a consolidated city-county, located in the South Platte River Valley on the western edge of the High Plains just east of the Front Range of the Rocky Mountains...
, Boulder
Boulder, Colorado
Boulder is the county seat and most populous city of Boulder County and the 11th most populous city in the U.S. state of Colorado. Boulder is located at the base of the foothills of the Rocky Mountains at an elevation of...
, Longmont
Longmont, Colorado
Longmont is a Home Rule Municipality in Boulder and Weld counties in the U.S. state of Colorado. Longmont is located in Northern Colorado. Longmont is the 13th most populous city in the State of Colorado. The word "Longmont" comes from Longs Peak, a prominent mountain named for explorer Stephen H....
, Aurora
Aurora, Colorado
City of Aurora is a Home Rule Municipality spanning Arapahoe, Adams, and Douglas counties in Colorado. Aurora is an eastern suburb of the Denver-Aurora-Broomfield, CO Metropolitan Statistical Area . The city is the third most populous city in the Colorado and the 56th most populous city in the...
and other areas in central Colorado. Area code 303 is overlaid
Overlay plan
In telephony, especially in North America, an overlay plan is the practice of introducing a new area code by applying it onto a geographic area that is already occupied by one or more existing area codes, resulting in two area codes serving the same area.- Methodology :Prior to the introduction of...
with area code 720, meaning that the same physical service area is served by both area codes (303 and 720) and that ten-digit dialing is required for all calls made within the service area.
Prior to March 5, 1988, all of Colorado was served by the 303 area code but as the population grew, an impending phone number shortage forced a split of the state's area codes. Area code 719
Area code 719
Image:Area_codes_CO.svg|right|Map of Colorado area codes in blue poly 67 8 381 26 380 108 356 107 352 131 343 130 340 107 326 102 320 104 301 104 301 85 282 85 287 77 263 77 259 84 216 79 204 102 182 125 177 144 191 151 199 177 180 203 168 207 166 219 151 219 149 229 167 226 168 238 186 238 196...
was split from 303 on March 5, 1988, and 970
Area code 970
Area Code 970: ColoradoImage:Area_codes_CO.svg|right|Map of Colorado area codes in blue #poly 67 8 381 26 380 108 356 107 352 131 343 130 340 107 326 102 320 104 301 104 301 85 282 85 287 77 263 77 259 84 216 79 204 102 182 125 177 144 191 151 199 177 180 203 168 207 166 219 151 219 149 229 167...
was split from the remaining 303 area on April 2, 1995, leaving 303 to cover its current area. 303 was overlaid with 720 on June 1, 1998.
With one exception (the Roggen
Roggen, Colorado
Roggen is an unincorporated town and a U.S. Post Office in Weld County, Colorado, United States. The Roggen Post Office has the ZIP Code 80652....
area, which has local calling only with itself, Brighton
Brighton, Colorado
Brighton is a Home Rule Municipality in Adams and Weld counties in the U.S. state of Colorado, and the county seat of Adams County. The United States Census Bureau estimates that the city population was 31,380 in 2008.-Geography:...
, and Wiggins
Wiggins, Colorado
Wiggins is a Statutory village in Morgan County, Colorado, United States. The population was 001 at the 2000 census.The community was established in 1882 as the Burlington railroad depot of Corona. Around 1900, Corona was renamed in honor of Oliver P. Wiggins, who served as a guide and scout for...
http://www.localcallingguide.com/lca_exch.php?exch=027320), the entire 303/720 area is a local calling zone, so long distance is not applied to any calls made from one phone to another within the area.
With the exception mentioned above, all users in the 303/720 area code must dial all ten digits to reach a destination phone, even if that phone is next door. Some users in the area have shortened the two area codes to a single digit with a slash for easy writing. So 303-555-1212 is written down as 3/555-1212. Since 303 is the dominant (and older) area code, if a number appears without an area code it is generally assumed to be 303.