One of Wisconsin's two original 1947 area codes, now serving the Milwaukee metropolitan core after repeated splits ceded most of its original territory.
The essentialsNumbering data · NumberResearch · as of 2026-09-18
Place
Milwaukee
Type
geographic
Status
in service
In service since
1947
Projected exhaust
2041 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 414 is
Milwaukee County, plus slivers of Waukesha and Washington counties..
Communities served wholly or partly by 414:
MilwaukeeMuskegoBrookfield
Only portions of Muskego and Brookfield fall within 414; the rest of those suburbs are in 262.
B · Relationships
How it relates to other codes
The codes 414 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 · 1955608Madison608 (Madison/southwest) split off from the original 414 territory.
Spawned · 1997920Green Bay / Fox CitiesEastern Wisconsin (Green Bay/Fox Valley) split off as 920.
Spawned · 1999262Southeastern Wisconsin (Waukesha/Racine/Kenosha)Southeastern Wisconsin suburbs split off as 262.
Related · 1947715Northern WisconsinThe other original 1947 Wisconsin code, covering the north.
What's changing. No overlay; 414 is a standalone numbering plan area after its splits.
C · History
How 414 got here
1947-10
Established as one of the two original Wisconsin area codes, covering most of southern and eastern Wisconsin.
Source: Wikipedia
1955
First split: Madison area became area code 608.
Source: Wikipedia
1997-07-26
Split: northern/eastern portion (Green Bay, Fox River Valley) became area code 920.
Source: Wikipedia
1999-09-25
Split: southeastern Wisconsin became area code 262.
Source: Wikipedia
2021-10-24
Mandatory ten-digit dialing began due to the nationwide 988 designation.
Source: Wikipedia
D · Capacity
How full it is
Prefixes assigned
567
Prefixes available
233
Thousands-blocks assigned
2,231
Prefix-assignment counts describe allocation to carriers, not how many individual numbers are in use. Full technical records: NumberResearch ↗.
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.
North American Numbers