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

HINSDALE prefixes in area code 312

NANPA records 11 assigned NXX blocks to rate center HINSDALE in area code 312, 1.4% of the 784 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. 1 holder holds those blocks, the largest being NEW CINGULAR WIRELESS PCS, LLC - IL (11). 10 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 331, 406, 413, 603 – overlay codes cover the same geography, so a rate center is served by all of them.

11 assigned blocks – 1.4% of 312
1 holders of record
10 of them pooled in 1,000-number lots

Prefixes assigned here

PrefixHolder of recordAssignedPooledIn service
312-301 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL – no yes
312-304 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL – yes yes
312-314 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL – yes yes
312-352 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL – yes yes
312-510 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL – yes yes
312-531 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL – yes yes
312-699 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL – yes yes
312-749 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL – yes yes
312-816 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL – yes yes
312-844 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL – yes yes
312-990 AT&T NEW CINGULAR WIRELESS PCS, LLC - IL – 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.

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 HINSDALE in area code 312?

11 blocks: 301, 304, 314, 352, 510, 531, 699, 749, 816, 844, 990. The table above gives the holder of each.

Which carriers have numbers in HINSDALE?

NEW CINGULAR WIRELESS PCS, LLC - IL (11 blocks). These are the holders on record; the carrier actually serving a given number can differ, because numbers move with their owners.

Is HINSDALE 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 312

All 784 prefixes in 312