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

ONTARIO prefixes in area code 315

NANPA records 4 assigned NXX blocks to rate center ONTARIO in area code 315, 0.5% of the 781 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. 3 holders hold those blocks, the largest being VERIZON NEW YORK, INC. (2), PAETEC ITEL, LLC (1), BANDWIDTH.COM CLEC, LLC - NY (1). The earliest assignment on record here is 2002-04-15 and the most recent 2018-08-15. 4 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 458, 541, 608, 680 – overlay codes cover the same geography, so a rate center is served by all of them.

4 assigned blocks – 0.5% of 315
3 holders of record
4 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
315-333 Windstream PAETEC ITEL, LLC 2002-04-15 yes yes
315-524 Verizon VERIZON NEW YORK, INC. – yes yes
315-791 Verizon VERIZON NEW YORK, INC. 2004-03-23 yes yes
315-997 Bandwidth BANDWIDTH.COM CLEC, LLC - NY 2018-08-15 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
VERIZON NEW YORK, INC. Verizon 2 50%
PAETEC ITEL, LLC Windstream 1 25%
BANDWIDTH.COM CLEC, LLC - NY Bandwidth 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 ONTARIO in area code 315?

4 blocks: 333, 524, 791, 997. The table above gives the holder of each.

Which carriers have numbers in ONTARIO?

VERIZON NEW YORK, INC. (2 blocks), PAETEC ITEL, LLC (1 block), BANDWIDTH.COM CLEC, LLC - NY (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is ONTARIO 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 315

All 781 prefixes in 315