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

CHASE prefixes in area code 443

NANPA records 6 assigned NXX blocks to rate center CHASE in area code 443, 0.8% of the 785 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. 5 holders hold those blocks, the largest being PAETEC ITEL, LLC (2), BANDWIDTH.COM CLEC, LLC - MD (1), TELEPORT COMMUNICATIONS AMERICA, LLC - MD (1). The earliest assignment on record here is 2001-05-10 and the most recent 2001-07-23. 6 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 codes 410, 620, 667 – overlay codes cover the same geography, so a rate center is served by all of them.

6 assigned blocks – 0.8% of 443
5 holders of record
6 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
443-228 Windstream PAETEC ITEL, LLC – yes yes
443-317 Bandwidth BANDWIDTH.COM CLEC, LLC - MD – yes yes
443-489 AT&T TELEPORT COMMUNICATIONS AMERICA, LLC - MD – yes yes
443-554 T-Mobile OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 2001-07-23 yes yes
443-581 Onvoy ONVOY, LLC - MD – yes yes
443-626 Windstream PAETEC ITEL, LLC 2001-05-10 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
PAETEC ITEL, LLC Windstream 2 33.3%
BANDWIDTH.COM CLEC, LLC - MD Bandwidth 1 16.7%
TELEPORT COMMUNICATIONS AMERICA, LLC - MD AT&T 1 16.7%
OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC T-Mobile 1 16.7%
ONVOY, LLC - MD Onvoy 1 16.7%

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 CHASE in area code 443?

6 blocks: 228, 317, 489, 554, 581, 626. The table above gives the holder of each.

Which carriers have numbers in CHASE?

PAETEC ITEL, LLC (2 blocks), BANDWIDTH.COM CLEC, LLC - MD (1 block), TELEPORT COMMUNICATIONS AMERICA, LLC - MD (1 block), OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC (1 block), ONVOY, LLC - MD (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is CHASE 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 443

All 785 prefixes in 443