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

WINTHROP prefixes in area code 617

NANPA records 5 assigned NXX blocks to rate center WINTHROP in area code 617, 0.7% of the 768 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 VERIZON NEW ENGLAND INC. (2), COMCAST IP PHONE, LLC (1), RCN TELECOM SERVICES, INC. - MA (1). 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 207, 315, 319, 507 – overlay codes cover the same geography, so a rate center is served by all of them.

5 assigned blocks – 0.7% of 617
4 holders of record
4 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
617-207 Comcast COMCAST IP PHONE, LLC – yes yes
617-329 RCN TELECOM SERVICES, INC. - MA – yes yes
617-539 Verizon VERIZON NEW ENGLAND INC. – yes yes
617-841 Lumen LEVEL 3 COMMUNICATIONS, LLC - MA – yes yes
617-846 Verizon VERIZON NEW ENGLAND INC. – 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
VERIZON NEW ENGLAND INC. Verizon 2 40%
COMCAST IP PHONE, LLC Comcast 1 20%
RCN TELECOM SERVICES, INC. - MA – 1 20%
LEVEL 3 COMMUNICATIONS, LLC - MA Lumen 1 20%

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 WINTHROP in area code 617?

5 blocks: 207, 329, 539, 841, 846. The table above gives the holder of each.

Which carriers have numbers in WINTHROP?

VERIZON NEW ENGLAND INC. (2 blocks), COMCAST IP PHONE, LLC (1 block), RCN TELECOM SERVICES, INC. - MA (1 block), LEVEL 3 COMMUNICATIONS, LLC - MA (1 block). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is WINTHROP 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 617

All 768 prefixes in 617