Prefix 414-377 — Milwaukee Zone 3, WI

NANPA CO code assignment, current as of July 28, 2026.

Area code
414
Prefix (NXX)
377
Rate center
Milwaukee Zone 3
State
Wisconsin
Time zone
Central
Code holder
LEVEL 3 COMMUNICATIONS, LLC - WI
OCN
5489
Pooled
Yes (thousands-block pooling)
Assigned
2002-12-16
LATA
356

Numbers in the 414-377 prefix are registered to the Milwaukee Zone 3 rate center in WI, inside area code 414. The prefix is the second block of a ten-digit US number (414-377-XXXX) and pins the number to a billing locality.

Code-holder of record: LEVEL 3 COMMUNICATIONS, LLC - WI (OCN 5489), assigned December 16, 2002. The prefix is pooled: its ten thousands-blocks can be shared among several carriers, so different 414-377 numbers may be served by different companies.

The rate center lies in the (Milwaukee-Waukesha, WI Metropolitan Statistical Area). The serving LATA is 356. Local time follows the Central zone.

Spoofing means this prefix on your screen doesn't guarantee a Milwaukee Zone 3 caller. Verify independently before trusting a request for money or data.

Neighboring prefixes

Prefixes adjacent to 414-377
PrefixRate centerCode holder
414-374 Milwaukee Zone 1 WISCONSIN BELL INC
414-375 Milwaukee Zone 4 LEVEL 3 COMMUNICATIONS, LLC - WI
414-376 Milwaukee Zone 5 LEVEL 3 COMMUNICATIONS, LLC - WI
414-378 Milwaukee Zone 1 NEW CINGULAR WIRELESS PCS, LLC - IL
414-379 Milwaukee Zone 1 NEW CINGULAR WIRELESS PCS, LLC - IL
414-380 Milwaukee Zone 1 UNITED STATES CELLULAR - WI

FAQ

Where is 414-377 located?

The prefix is assigned to the Milwaukee Zone 3 rate center in WI, area code 414. It is part of the (Milwaukee-Waukesha, WI Metropolitan Statistical Area).

Which company owns 414-377 numbers?

LEVEL 3 COMMUNICATIONS, LLC - WI holds the code, but the prefix is pooled — individual thousands-blocks can be assigned to other carriers, and numbers may be ported to any provider.

Is a call from 414-377 safe to answer?

The prefix itself says nothing about the caller. Legitimate Milwaukee Zone 3 businesses and spoofed robocalls can both display it. Never share personal data with an unverified inbound caller.