Area Code 412
Pennsylvania
Area code 412 serves Pennsylvania, primarily Pittsburgh, in the Eastern Time (ET) time zone. It has served the region since 01-Jan-1947.
Published: Last reviewed: Verified against NANPA and FCC records
Overlay Area Code
This area code shares its geographic footprint with an overlay code, so the same cities are served by two area codes. Because overlays leave existing numbers untouched, this region's relief planning favors adding codes over redrawing boundaries.
The codes serving this same region: area code 878 (Pittsburgh).
With prefix utilization already at 95.3%, numbering resources here are under sustained pressure — context that explains why overlays were introduced.
In service since: 01-Jan-1947
Area Code Splits
One area code has been carved out of this code's original territory through a geographic split. Each split was a relief action: as demand grew, part of the region was reassigned to a new code rather than overlaying the whole territory.
Split into: area code 724 (Monroeville).
Demographics & Economics
- Total Population
- 1,277,708
- Population Density
- 1,057 people/sq miabove U.S. average (U.S.: 95 people/sq mi)
- Median Household Income
- $78,548near U.S. median (U.S.: $80,734)
- Poverty Rate
- 11.3%near U.S. average (U.S.: 12.5%)
- Unemployment Rate
- 5.0%near U.S. average (U.S.: 5.2%)
- Education Attainment
- Bachelor's Degree+44.1%above U.S. average (U.S.: 35.7%)High School or Lower27.9%
Statistics are population-weighted aggregations from Census ACS 5-year estimates. Population figures are approximate — see Sources & Methodology for details on how area code populations are derived.
See how this area code compares to all US area codes in the income ranking and density ranking.
Time Zone
- Eastern Time (ET)
NANPA Relief Status
According to the latest NANPA analysis (July 2026), this area code is not currently listed as exhausting within the next 36 months. No relief planning is in progress for this NPA.
Source: NANPA NPA Relief Planning Reports · See all relief planning statuses
Current Time
Prefix Utilization
Geographic Coverage
State
PA
Major Cities
- Pittsburgh
- Bethel Park
- Monroeville
- Plum
- Allison Park
- New Castle
- Baldwin
- Murrysville
- West Mifflin
- McKeesport
- Hermitage
- Franklin Park
- Whitehall
- Greensburg
- Indiana
- Wilkinsburg
- Carnot-Moon
- Washington
- Butler
- Sharon
- Jefferson Hills
- New Kensington
- Lower Burrell
- Munhall
and 455 more cities
Historical Timeline of Area Code 412
On January 1, 1947, area code 412 entered service as one of the original 77 US NANP area codes, covering the entire southwestern corner of Pennsylvania from Butler County to the West Virginia border. The code served this region for over 50 years before a 1998 split reshaped its boundaries. Source: NANPA
Key milestones:
- 1947: Created as one of the original 77 US NPAs in the North American Numbering Plan, assigned to southwestern Pennsylvania Source: Wikidata
- 1997: Pennsylvania PUC ordered a geographic split on July 15, 1997 (Docket P-00961027), dividing 412 into 412 and area code 724. Pittsburgh metro retained 412; surrounding communities transferred to 724 Source: PA PUC
- 1998: 724 activated on February 1, 1998, transforming 412 into a doughnut-shaped code surrounded by 724. Permissive dialing ended April 30, 1998 Source: NANPA PL-091
- 1998: FCC issued declaratory ruling FCC 98-224 on September 28, 1998, finding that the PA PUC's split order exceeded state jurisdiction over numbering administration Source: Federal Register
- 1999: NANPA declared 412 in jeopardy due to number exhaustion from cell phone and pager proliferation Source: NANPA PL-222
- 2000: Industry consensus reached January 19, 2000 for an all-services multiple overlay. NANPA PL-222 assigned 878 as relief code covering both 412 and 724 Source: NANPA PL-222
- 2001: 878 overlay activated August 17, 2001. Mandatory 10-digit dialing across southwestern Pennsylvania since July 12, 2001 Source: NANPA PL-222
- 2013: First 878 numbers assigned, initially only in the 724 area until 2015
Regulatory History
Area code 412 has been shaped by a notable jurisdictional conflict between the Pennsylvania PUC and the FCC over who controls numbering administration. The dispute, resolved in FCC 98-224, established that state commissions cannot unilaterally order area code splits without federal oversight. Source: Federal Register
| Year | Event | Docket | Regulatory Action & Impact |
|---|---|---|---|
| 1947 | NANP Inception | AT&T / Bell System | Area code 412 established as one of the original 77 US NANP area codes, assigned to PA. |
| 1997 | PA PUC Split Order | P-00961027 | Pennsylvania PUC ordered geographic split of 412 into 412/724 on July 15, 1997. The urban core stayed with 412 while outer counties moved to 724. The order directed carriers to prepare for the split without prior FCC approval. Source: PA PUC |
| 1998 | 724 Split Activation | NANPA PL-091 | NANPA implemented the split on February 1, 1998 per Planning Letter PL-091. Permissive dialing ran through April 30, 1998. The split reduced 412's footprint to Allegheny County and small portions of adjacent counties. Source: NANPA PL-091 |
| 1998 | FCC Declaratory Ruling | FCC 98-224 | FCC ruled on September 28, 1998 that the PA PUC's split order exceeded state jurisdiction over numbering administration. The FCC asserted federal preemption under the Telephone Consumer Protection Act. Effective December 16, 1998. Source: Federal Register |
| 2000 | 878 Overlay Assigned | NANPA PL-222 | NANPA assigned 878 as an all-services multiple overlay for both 412 and 724. Industry consensus reached January 19, 2000. Permissive 10-digit dialing began July 17, 2000. Source: NANPA PL-222 |
| 2001 | 878 Overlay Activated | NANPA PL-222 | 878 overlay activated August 17, 2001. Mandatory 10-digit dialing began July 12, 2001 across southwestern Pennsylvania. First 878 numbers not assigned until 2013. Source: NANPA PL-222 |
County Coverage
Population-weighted county share based on aggregated ZCTA population (100% = total mapped population for area code 412).
| County | Population | Share |
|---|---|---|
| Allegheny, PA | 1,119,735 | 87.6% |
| Washington, PA | 80,953 | 6.3% |
| Westmoreland, PA | 55,071 | 4.3% |
| Beaver, PA | 21,949 | 1.7% |
Area Code 412 Family Tree
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Area code 412 was originally assigned in 01-Jan-1947 to serve PA. Over the years, it has generated 2 descendant area codes through a combination of geographic splits and overlays as demand for telephone numbers grew.
Call Context
This area code serves a major metropolitan region with high population density in PA. The primary city is Pittsburgh.
Nearby Area Codes
Area codes geographically closest to 412.
Other Area Codes in Pennsylvania
Area codes that also serve Pennsylvania, linked for easy comparison.