Prefix 410-402 — Catonsville, MD

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

The 410-402 prefix belongs to area code 410 and is anchored to the Catonsville rate center (MD). In NANP terms, the prefix — or NXX — determines the rate center a number is billed against.

Catonsville is part of the Baltimore-Columbia-Towson, MD Metropolitan Statistical Area. For routing purposes it sits in LATA 238. Numbers here keep Eastern time.

The assigned code holder is MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD, operating company number 7228. 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 410-402 is not proof the call came from Catonsville: 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

FAQ

Where is 410-402 located?

The prefix is assigned to the Catonsville rate center in MD, area code 410. It is part of the Baltimore-Columbia-Towson, MD Metropolitan Statistical Area.

Which company owns 410-402 numbers?

MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 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 410-402 safe to answer?

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