North American Numbers Source-cited · ownership disclosed
Area code
248
In service
United States · since 1997

Oakland County

Oakland County (northern Metro Detroit), created by a 1997 split of area code 810 and overlaid by 947 since 2002.

The essentials Numbering data · NumberResearch · as of 2026-09-18
Place
Oakland County
Type
geographic
Status
in service
In service since
1997
Projected exhaust
2065 Q4

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 248 is

Oakland County, Michigan (plus small parts of Wayne County — Livonia/Northville)..

Communities served wholly or partly by 248:

PontiacTroySouthfieldFarmington HillsRochester HillsRoyal OakNoviAuburn HillsBirminghamBloomfield HillsWalled Lake

Also covers portions of Livonia and Northville in Wayne County.

B · Relationships

How it relates to other codes

The codes 248 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?

Split from · 1997 810 Flint / The Thumb Split from 810.
Overlay · 2002 947 Oakland County (overlay) All-services overlay of the same 248 geography.
Related 586 Macomb County Macomb County to the east.
What's changing. Overlaid by 947 since 2002; 10-digit dialing mandatory.
C · History

How 248 got here

1997
Established through a split of area code 810 for Oakland County (permissive dialing began May 10, 1997).
Source: Wikipedia
2002-01-26
Ten-digit dialing mandatory after 947 overlay permissive period ended.
Source: Wikipedia
D · Capacity

How full it is

Prefixes assigned
799
Prefixes available
1
Thousands-blocks assigned
2,911

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

Compare 248 with another code →
Sources
Wikipedia ↗
Area codes 248 and 947
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.