North American Numbers Source-cited · ownership disclosed
Area code
412
In service
United States · since 1947

Pittsburgh

One of the original 1947 area codes, 412 now serves Pittsburgh and most of Allegheny County after 724 split off in 1998; it is overlaid by 878.

The essentials Numbering data · NumberResearch · as of 2026-09-18
Place
Pittsburgh
Type
geographic
Status
in service
In service since
1947
Projected exhaust
2038 Q2

Status, dates and counts are read from NumberResearch (NANPA / CNAC / FCC records). Assignment records show initial assignees, not the carrier serving a number today.

A · Where it is

Where 412 is

Pittsburgh metro / Allegheny County.

Communities served wholly or partly by 412:

Pittsburgh

Pittsburgh, most of surrounding Allegheny County, and small portions of Washington and Westmoreland counties.

B · Relationships

How it relates to other codes

The codes 412 was split from, spawned, or shares its area with. A split divides the map and changes some numbers; an overlay shares the same ground and changes none — what's the difference?

Spawned · 1998 724 Southwestern PA On Feb 1, 1998 SW PA outside Allegheny County split off to 724.
Overlay · 2001 878 Pittsburgh/SW PA (overlay) 878 overlays both 412 and 724.
What's changing. Overlaid by 878 (shared with 724); 10-digit dialing mandatory.
C · History

How 412 got here

1947
Established as an original area code for SW Pennsylvania.
Source: Wikipedia 412
1998-02-01
724 split off, reducing 412 to Allegheny County core.
Source: Wikipedia 412
2001-08-17
878 overlay implemented.
Source: Wikipedia 412
D · Capacity

How full it is

Prefixes assigned
783
Prefixes available
17
Thousands-blocks assigned
3,152

Prefix-assignment counts describe allocation to carriers, not how many individual numbers are in use. Full technical records: NumberResearch ↗.

Compare 412 with another code →
Sources
Wikipedia ↗
Area code 412
NumberResearch.org ↗
Live status, dates, assignment counts and exhaust forecast — data as of 2026-09-18 (CC BY 4.0).

Place, relationships and history above are compiled by North American Numbers from the sources listed and last checked 2026-09-18. A check date is not an expert review — see how this is made. Flag an error.