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

EUREKA prefixes in area code 775

NANPA records 10 assigned NXX blocks to rate center EUREKA in area code 775, 1.7% of the 601 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. 6 holders hold those blocks, the largest being ONVOY, LLC - NV (5), NEVADA BELL (1), UTILITY TELECOM GROUP, LLC - NV (1). The earliest assignment on record here is 2001-07-10 and the most recent 2025-03-26. 5 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 309, 369, 406, 435 – overlay codes cover the same geography, so a rate center is served by all of them.

10 assigned blocks – 1.7% of 775
6 holders of record
5 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
775-237 AT&T NEVADA BELL – yes yes
775-254 Onvoy ONVOY, LLC - NV – no yes
775-270 UTILITY TELECOM GROUP, LLC - NV 2001-07-10 no yes
775-318 AT&T NEW CINGULAR WIRELESS PCS, LLC 2002-08-29 yes yes
775-367 Onvoy ONVOY, LLC - NV – no yes
775-522 Onvoy ONVOY, LLC - NV – no yes
775-551 Onvoy ONVOY, LLC - NV – yes yes
775-590 Charter ONVOY SPECTRUM, LLC 2023-10-24 yes yes
775-595 RINGER MOBILE, INC. 2025-03-26 yes yes
775-640 Onvoy ONVOY, LLC - NV – no 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
ONVOY, LLC - NV Onvoy 5 50%
NEVADA BELL AT&T 1 10%
UTILITY TELECOM GROUP, LLC - NV – 1 10%
NEW CINGULAR WIRELESS PCS, LLC AT&T 1 10%
ONVOY SPECTRUM, LLC Charter 1 10%
RINGER MOBILE, INC. – 1 10%

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 EUREKA in area code 775?

10 blocks: 237, 254, 270, 318, 367, 522, 551, 590, 595, 640. The table above gives the holder of each.

Which carriers have numbers in EUREKA?

ONVOY, LLC - NV (5 blocks), NEVADA BELL (1 block), UTILITY TELECOM GROUP, LLC - NV (1 block), NEW CINGULAR WIRELESS PCS, LLC (1 block), ONVOY SPECTRUM, LLC (1 block), RINGER MOBILE, INC. (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is EUREKA 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 775

All 601 prefixes in 775