No Results Found!
238 Related Articles

Area codes 613 and 343

613613, 343343
It shares the same calling area as Hull, its twin city in Quebec, even though Ottawa was in area code 613 and Hull was in area code 819.
Area code 613 and overlay area code 343 are area codes for Ottawa and surrounding Eastern Ontario, Canada, in the North American Numbering Plan (NANP).

Area codes 703 and 571

703571571 & 703
Every number in Maryland's area code 301 and northern Virginia's 703 was given a "hidden" phone number consisting of the same number in the D.C.'s area code 202, essentially making area code 202 an overlay for the entire region.
Area code 571 was created on March 1, 2000 as an overlay to 703.

Area code 206

206area code
For example, the original area code for the entire state of Washington was 206; today 206 applies to only the city of Seattle and the immediate vicinity.
As of January 2017, this numbering plan area was one of the last urbanized areas in the North American Numbering Plan without a code overlay, meaning telephone calls within Seattle could still be originated by seven-digit dialing.

Split plan

split
This practice became known as a split plan.
As a result, in the mid-1990s, the North American Numbering Plan introduced overlay plans, which apply multiple area codes to the same area.

Area code 202

202Area codes in Washington, D.C.
Every number in Maryland's area code 301 and northern Virginia's 703 was given a "hidden" phone number consisting of the same number in the D.C.'s area code 202, essentially making area code 202 an overlay for the entire region.
As of 2012, no plans exist to overlay the 202 area code, as NANPA estimates the current supply of numbers is sufficient at least to the year 2022.

Area code 917

917 917
The first use of this solution was in New York City, where area code 917 was added to Manhattan's 212 and the outer boroughs' 718.
It was the first cellular/pager/voicemail area code for the city and is an overlay to Manhattan's 212/646/332 and the other four boroughs' 718/347/929.

Area codes 212, 646, and 332

212212, 332, 646area code 212
The first use of this solution was in New York City, where area code 917 was added to Manhattan's 212 and the outer boroughs' 718.
In 1992, the entire city was overlaid with area code 917, which originally had been planned for only the Bronx and mobile service.

Local call

local phone calls
Most overlay plans introduced the inconvenience of mandatory ten-digit dialing, in which the area code must always be included even when dialing local calls.
However, this is not true in parts of the United States and Canada that are subject to overlay plans or many countries in Europe that require closed dialing plans.

Area codes 301 and 240

301240 & 301240
Every number in Maryland's area code 301 and northern Virginia's 703 was given a "hidden" phone number consisting of the same number in the D.C.'s area code 202, essentially making area code 202 an overlay for the entire region.
To solve this problem, area code 240 was introduced on June 1, 1997, as the state's first overlay area code.

List of California area codes

CaliforniaArea code(s)Area codes in California
Connecticut, Illinois, Oregon, New Jersey, Massachusetts, Maryland, Pennsylvania, Texas, and, more recently, California have also implemented many overlays.
310 – Santa Monica, Malibu, Pacific Palisades, Compton, Torrance, Beverly Hills, Catalina Island; the southwestern portion of Los Angeles County. (Split from 213 on November 2, 1991; overlaid by 424 on August 26, 2006)

List of Georgia area codes

GeorgiaArea codes in the state of Georgia
For example, much of Ohio is covered by large overlay complexes, as is northern Georgia.
678 was given to both the city and its suburbs in January 1998, becoming the first overlay area code in the state, and forcing mandatory ten-digit dialing for all calls.

List of Pennsylvania area codes

Pennsylvania
Connecticut, Illinois, Oregon, New Jersey, Massachusetts, Maryland, Pennsylvania, Texas, and, more recently, California have also implemented many overlays.
223: An overlay of 717

Area codes 208 and 986

208986area code 208
Idaho followed this precedent in 2017, overlaying area code 208 with 986.
It was Idaho's sole area code until 2017, when 986 was added as an overlay for the entire state.

Ten-digit dialing

10-digit dialingten-digit diallingten digits
Most overlay plans introduced the inconvenience of mandatory ten-digit dialing, in which the area code must always be included even when dialing local calls.
The introduction of overlay plans as a means to reduce the need for phone numbers to change as a result of adding new area codes meant that one geographic area could be associated with more than one area code.

Area codes 905, 289, and 365

905 and 289905905, 289, 365
The area code for Metro Toronto, 416, was on the verge of exhaustion only five years after the suburbs split off as area code 905 in 1993.
905 is the main area code, while 289 and 365 are overlay codes covering the same territory.

Area codes 514 and 438

514 and 438(514) and (438)514
Partly due to these factors, the numbering plan areas corresponding to four of the five largest Canadian markets (416 in Toronto, 514 in Montreal, 604 in Vancouver, and 403 in Calgary) were split in the 1990s.
438 is an overlay area code covering the same area.

Area codes 304 and 681

304 & 681304304/681
The first example of an entire state previously only served by a single code being overlaid was in West Virginia, which had been served with area code 304 since the inception of the North American Numbering Plan.
It was overlaid with area code 681, effective March 28, 2009.

Area codes 416, 647, and 437

416416, 647416, 647, 437
Partly due to these factors, the numbering plan areas corresponding to four of the five largest Canadian markets (416 in Toronto, 514 in Montreal, 604 in Vancouver, and 403 in Calgary) were split in the 1990s.
Another option was an overlay area code covering the same area as 416.

Area code 604

604+1-604area code
Partly due to these factors, the numbering plan areas corresponding to four of the five largest Canadian markets (416 in Toronto, 514 in Montreal, 604 in Vancouver, and 403 in Calgary) were split in the 1990s.
On November 3, 2001, area code 778 was implemented as a concentrated overlay for the two largest regional districts in the Lower Mainland, Metro Vancouver and the Fraser Valley Regional District.

Area code 312

312312 area codearea code
Multiple-area distributed overlay: two or more area codes gain a single new area code covering such an area. Examples include 872 in Chicago, Illinois (over 312 and 773) and 587 in Alberta (over 403 and 780).
Both area codes are overlaid with area code 872.

Area codes 778 and 236

778236area code 778
Boundary-extension overlay: a neighboring area code (either an overlay code or single primary area code) is expanded to serve the area as well. Examples include 321 over 407 in central Florida and 778 over 250 in British Columbia. In 1999 281 was the first to do so, unifying with 713 in Houston; later that year 972 unified with 214; followed by 323 unifying with 213 in L.A. in 2017.
Area codes 778 and 236 are overlay area codes for the Canadian province of British Columbia.

Area codes 587 and 825

587+1-587587, 825
Multiple-area distributed overlay: two or more area codes gain a single new area code covering such an area. Examples include 872 in Chicago, Illinois (over 312 and 773) and 587 in Alberta (over 403 and 780).
The new area codes overlay 403 and 780 simultaneously, covering the entire province, and make 10-digit dialing necessary throughout Alberta.

Area code 807

807
By 2013, seven-digit dialing had been eliminated in every Canadian numbering plan area except in the country's three Arctic territories (area code 867), a large but sparsely populated area in northwestern Ontario (area code 807), New Brunswick (area code 506), and Newfoundland and Labrador (area code 709).
In the early 21st century, as 705 neared exhaustion, CNAC briefly considered "erasing" the 807-705 boundary and turning 807 into an overlay for all of Ontario north and west of the Golden Horseshoe.

Area codes 713, 281, 346, and 832

281713832
Boundary-extension overlay: a neighboring area code (either an overlay code or single primary area code) is expanded to serve the area as well. Examples include 321 over 407 in central Florida and 778 over 250 in British Columbia. In 1999 281 was the first to do so, unifying with 713 in Houston; later that year 972 unified with 214; followed by 323 unifying with 213 in L.A. in 2017.
713 is the main area code, while 281, 832 and 346 are overlay codes covering the same area.

List of area code overlays

List of area code overlays
The North American Numbering Plan Administration maintains the definitive list of overlay plans of area codes in the United States.