NumberingData
Verified Nov 1, 2026 · Source: NANPA CO Code Assignment Records

MENDHAM prefixes in area code 973

NANPA records 4 assigned NXX blocks to rate center MENDHAM in area code 973, 0.5% of the 779 blocks assigned in the code. A rate center is the billing geography a block is allocated to – NANPA truncates the name to ten characters, so read it as a NANPA label rather than a town. 4 holders hold those blocks, the largest being LEVEL 3 COMMUNICATIONS, LLC - NJ (1), CABLEVISION LIGHTPATH, INC. - NJ (1), VERIZON NEW JERSEY, INC. (1). The earliest assignment on record here is 2001-01-09 and the most recent 2001-01-09. 3 of them are in thousands-block pooling, so those prefixes are shared between carriers in 1,000-number lots. The same rate center name also appears in area code 862 – overlay codes cover the same geography, so a rate center is served by all of them.

4 assigned blocks – 0.5% of 973
4 holders of record
3 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
973-370 Lumen LEVEL 3 COMMUNICATIONS, LLC - NJ – yes yes
973-531 Altice CABLEVISION LIGHTPATH, INC. - NJ 2001-01-09 yes yes
973-543 Verizon VERIZON NEW JERSEY, INC. – no yes
973-813 AT&T TELEPORT COMMUNICATIONS AMERICA, LLC - NJ – yes yes

The holder is who received the block from the numbering administrator. It is not necessarily the carrier serving a given number: numbers move with their owners, and a pooled block is shared.

Who holds the blocks

HolderBrandBlocksShare here
LEVEL 3 COMMUNICATIONS, LLC - NJ Lumen 1 25%
CABLEVISION LIGHTPATH, INC. - NJ Altice 1 25%
VERIZON NEW JERSEY, INC. Verizon 1 25%
TELEPORT COMMUNICATIONS AMERICA, LLC - NJ AT&T 1 25%

Same rate center in other codes

Overlay codes cover the same geography, so one rate center is served by all of them.

Frequently asked

Which prefixes belong to MENDHAM in area code 973?

4 blocks: 370, 531, 543, 813. The table above gives the holder of each.

Which carriers have numbers in MENDHAM?

LEVEL 3 COMMUNICATIONS, LLC - NJ (1 block), CABLEVISION LIGHTPATH, INC. - NJ (1 block), VERIZON NEW JERSEY, INC. (1 block), TELEPORT COMMUNICATIONS AMERICA, LLC - NJ (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is MENDHAM a city?

It is a rate center – the unit NANPA allocates number blocks to. Its name is abbreviated to ten characters and is not necessarily a settlement: we print it as recorded rather than guess at the full name.

Other rate centers in 973

All 779 prefixes in 973