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

WASHINGTON prefixes in area code 878

NANPA records 8 assigned NXX blocks to rate center WASHINGTON in area code 878, 4.2% of the 191 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 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - PA (4), ONVOY, LLC - PA (2), TELNYX LLC (1). The earliest assignment on record here is 2015-02-12 and the most recent 2026-05-14. 8 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 207, 252, 309, 319 – overlay codes cover the same geography, so a rate center is served by all of them.

8 assigned blocks – 4.2% of 878
4 holders of record
8 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
878-212 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - PA 2017-11-30 yes yes
878-218 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - PA 2015-02-12 yes yes
878-226 Onvoy ONVOY, LLC - PA 2021-01-28 yes yes
878-229 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - PA 2020-02-05 yes yes
878-243 Telnyx TELNYX LLC 2021-02-05 yes yes
878-297 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL 2025-10-01 yes yes
878-545 Verizon CELLCO PARTNERSHIP DBA VERIZON WIRELESS - PA 2026-05-14 yes yes
878-880 Onvoy ONVOY, LLC - PA 2020-05-14 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
CELLCO PARTNERSHIP DBA VERIZON WIRELESS - PA Verizon 4 50%
ONVOY, LLC - PA Onvoy 2 25%
TELNYX LLC Telnyx 1 12.5%
NEW CINGULAR WIRELESS PCS, LLC - IL AT&T 1 12.5%

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 WASHINGTON in area code 878?

8 blocks: 212, 218, 226, 229, 243, 297, 545, 880. The table above gives the holder of each.

Which carriers have numbers in WASHINGTON?

CELLCO PARTNERSHIP DBA VERIZON WIRELESS - PA (4 blocks), ONVOY, LLC - PA (2 blocks), TELNYX LLC (1 block), NEW CINGULAR WIRELESS PCS, LLC - IL (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is WASHINGTON 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 878

All 191 prefixes in 878