Pittsburgh/SW PA (overlay)

878 is a single overlay covering two distinct numbering plan areas — 412 (Pittsburgh/Allegheny) and 724 (surrounding SW Pennsylvania) — activated in 2001.

The essentials Numbering data · NumberResearch · as of 2026-09-18

Place

Type

geographic

Status

in service

In service since

2001

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 878 is

Southwestern Pennsylvania (overlays both 412 and 724 territories).

Communities served wholly or partly by 878:

PittsburghWashingtonGreensburgButlerNew Castle

Overlays the combined 412 + 724 footprint.

B · Relationships

How it relates to other codes

The codes 878 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?

Overlay · 2001 412 Pittsburgh 878 overlays 412.

Overlay · 2001 724 Southwestern PA 878 overlays 724.

What's changing. Active dual overlay of 412 and 724.

C · History

How 878 got here

2001-08-17

Activated as overlay on both 412 and 724.

Source: Wikipedia 878

2013-04

First 878 numbers actually assigned (~12 years after activation).

Source: Wikipedia 878

D · Capacity

How full it is

Prefixes assigned

204

Prefixes available

596

Thousands-blocks assigned

1,442

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

Compare 878 with another code →

Sources

Wikipedia ↗

Area code 878

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.