Prefix 305-504 — Keys, FL

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

Area code
305
Prefix (NXX)
504
Rate center
Keys
State
Florida
Time zone
Eastern
Code holder
OMNIPOINT MIAMI E LICENSE, LLC
OCN
6889
Pooled
Yes (thousands-block pooling)
Assigned
2012-11-21
LATA
460

The 305-504 prefix belongs to area code 305 and is anchored to the Keys rate center (FL). In NANP terms, the prefix — or NXX — determines the rate center a number is billed against.

Keys is part of the Miami-Fort Lauderdale-Pompano-West Palm Beach, FL Metropolitan Statistical Area. For routing purposes it sits in LATA 460. Numbers here keep Eastern time.

The assigned code holder is OMNIPOINT MIAMI E LICENSE, LLC, operating company number 6889, assigned November 21, 2012. This is a pooled prefix — expect numbers within it to be split across more than one carrier in 1,000-number blocks.

Caller ID showing 305-504 is not proof the call came from Keys: spoofing and porting both detach numbers from their origin. To verify a caller, hang up and dial the organization's published number, and report suspicious calls to the FTC.

Neighboring prefixes

Prefixes adjacent to 305-504
PrefixRate centerCode holder
305-501 Keys LEVEL 3 COMMUNICATIONS, LLC - FL
305-502 North Dade OMNIPOINT MIAMI E LICENSE, LLC
305-503 Miami PAETEC ITEL, LLC
305-505 Miami NEW CINGULAR WIRELESS PCS, LLC - GA
305-506 Perrine MCIMETRO ACCESS TRANSMISSION SERVICES LLC - FL
305-507 Miami MCIMETRO ACCESS TRANSMISSION SERVICES LLC - FL

FAQ

Where is 305-504 located?

The prefix is assigned to the Keys rate center in FL, area code 305. It is part of the Miami-Fort Lauderdale-Pompano-West Palm Beach, FL Metropolitan Statistical Area.

Which company owns 305-504 numbers?

OMNIPOINT MIAMI E LICENSE, LLC 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 305-504 safe to answer?

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