NumberResearchRecent thousands-block assignments
11 blocks assigned in the last 30 days · from the daily NANPA thousands-block report, 09/20/2026
Most carrier growth happens here, not at the prefix level: under number pooling, carriers receive individual 1,000-number blocks (e.g. 626-470-0XXX) within already-assigned prefixes. Assignments are initial assignments — the current serving carrier of individual numbers may differ due to portability.
Most active assignees, last 30 days — NPA 331
New assignments by month
Sep 2026
Aug 2026
Jul 2026
Jun 2026
May 2026
Apr 2026
Mar 2026
Feb 2026
Jan 2026
Dec 2025
Nov 2025
Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2017-09-01 | 331-219-7XXX | 7000–7999 | Assigned | FIRST COMMUNICATIONS, LLC | 460K | AURORA | IL |
| 2017-08-24 | 331-255-0XXX | 0000–0999 | Assigned | ONVOY, LLC | 224C | AURORA | IL |
| 2017-08-24 | 331-255-1XXX | 1000–1999 | Assigned | ONVOY, LLC | 224C | AURORA | IL |
| 2017-08-24 | 331-255-2XXX | 2000–2999 | Assigned | ONVOY, LLC | 224C | AURORA | IL |
| 2017-08-24 | 331-255-3XXX | 3000–3999 | Assigned | ONVOY, LLC | 224C | AURORA | IL |
| 2017-08-24 | 331-255-4XXX | 4000–4999 | Assigned | ONVOY, LLC | 224C | AURORA | IL |
| 2017-08-15 | 331-707-5XXX | 5000–5999 | Assigned | COMCAST IP PHONE, LLC | 318J | AURORA | IL |
| 2017-08-11 | 331-233-8XXX | 8000–8999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL | 6333 | DOWNERSGRV | IL |
| 2017-08-11 | 331-998-8XXX | 8000–8999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL | 6333 | DOWNERSGRV | IL |
| 2017-08-10 | 331-232-7XXX | 7000–7999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | W CHICAGO | IL |
| 2017-08-10 | 331-232-9XXX | 9000–9999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | W CHICAGO | IL |
| 2017-08-08 | 331-231-9XXX | 9000–9999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | NAPERVILLE | IL |
| 2017-08-07 | 331-814-1XXX | 1000–1999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL | 6333 | NAPERVILLE | IL |
| 2017-08-07 | 331-814-8XXX | 8000–8999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL | 6333 | NAPERVILLE | IL |
| 2017-07-28 | 331-707-6XXX | 6000–6999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | AURORA | IL |
| 2017-07-27 | 331-233-9XXX | 9000–9999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | DOWNERSGRV | IL |
| 2017-07-10 | 331-401-0XXX | 0000–0999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL | 6333 | NAPERVILLE | IL |
| 2017-07-05 | 331-315-4XXX | 4000–4999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | LOMBARD | IL |
| 2017-06-30 | 331-219-6XXX | 6000–6999 | Assigned | ONVOY, LLC | 224C | AURORA | IL |
| 2017-06-14 | 331-236-0XXX | 0000–0999 | Assigned | ONVOY, LLC | 224C | WHEATON | IL |
| 2017-06-13 | 331-757-1XXX | 1000–1999 | Assigned | ONVOY, LLC | 224C | LEMONT | IL |
| 2017-06-09 | 331-226-0XXX | 0000–0999 | Assigned | ONVOY, LLC | 224C | NAPERVILLE | IL |
| 2017-06-09 | 331-226-1XXX | 1000–1999 | Assigned | ONVOY, LLC | 224C | NAPERVILLE | IL |
| 2017-06-06 | 331-233-1XXX | 1000–1999 | Assigned | ONVOY, LLC | 224C | DOWNERSGRV | IL |
| 2017-06-01 | 331-707-0XXX | 0000–0999 | Assigned | ACCESS ONE, INC. - IL | 5447 | AURORA | IL |
| 2017-05-31 | 331-227-2XXX | 2000–2999 | Assigned | T-MOBILE USA, INC. | 6529 | SUGARGROVE | IL |
| 2017-05-31 | 331-227-3XXX | 3000–3999 | Assigned | T-MOBILE USA, INC. | 6529 | SUGARGROVE | IL |
| 2017-05-10 | 331-219-8XXX | 8000–8999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL | 6333 | AURORA | IL |
| 2017-05-10 | 331-219-9XXX | 9000–9999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL | 6333 | AURORA | IL |
| 2017-05-03 | 331-226-2XXX | 2000–2999 | Assigned | COMCAST IP PHONE, LLC | 318J | NAPERVILLE | IL |
| 2017-05-03 | 331-757-4XXX | 4000–4999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC - IL | 7196 | LEMONT | IL |
| 2017-04-26 | 331-310-9XXX | 9000–9999 | Assigned | TELNYX LLC | 073H | BIG ROCK | IL |
| 2017-04-18 | 331-771-3XXX | 3000–3999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | ST CHARLES | IL |
| 2017-04-18 | 331-871-4XXX | 4000–4999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | W CHICAGO | IL |
| 2017-04-18 | 331-871-6XXX | 6000–6999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | W CHICAGO | IL |
| 2017-04-18 | 331-901-3XXX | 3000–3999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | ST CHARLES | IL |
| 2017-04-12 | 331-227-1XXX | 1000–1999 | Assigned | TELNYX LLC | 073H | SUGARGROVE | IL |
| 2017-04-12 | 331-252-1XXX | 1000–1999 | Assigned | TELNYX LLC | 073H | WARRENVL | IL |
| 2017-04-12 | 331-315-0XXX | 0000–0999 | Assigned | TELNYX LLC | 073H | LOMBARD | IL |
| 2017-04-12 | 331-717-7XXX | 7000–7999 | Assigned | TELNYX LLC | 073H | OSWEGO | IL |
| 2017-04-12 | 331-757-0XXX | 0000–0999 | Assigned | TELNYX LLC | 073H | LEMONT | IL |
| 2017-04-12 | 331-871-9XXX | 9000–9999 | Assigned | TELNYX LLC | 073H | W CHICAGO | IL |
| 2017-04-11 | 331-771-4XXX | 4000–4999 | Assigned | TELNYX LLC | 073H | ST CHARLES | IL |
| 2017-04-06 | 331-227-8XXX | 8000–8999 | Assigned | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL | 6333 | SUGARGROVE | IL |
| 2017-04-06 | 331-230-9XXX | 9000–9999 | Assigned | T-MOBILE USA, INC. | 6529 | AURORA | IL |
| 2017-04-06 | 331-236-8XXX | 8000–8999 | Assigned | T-MOBILE USA, INC. | 6529 | WHEATON | IL |
| 2017-04-06 | 331-236-9XXX | 9000–9999 | Assigned | T-MOBILE USA, INC. | 6529 | WHEATON | IL |
| 2017-03-30 | 331-806-0XXX | 0000–0999 | Assigned | T-MOBILE USA, INC. | 6529 | WHEATON | IL |
| 2017-03-30 | 331-806-9XXX | 9000–9999 | Assigned | T-MOBILE USA, INC. | 6529 | WHEATON | IL |
| 2017-03-29 | 331-757-2XXX | 2000–2999 | Assigned | TELEPORT COMMUNICATIONS AMERICA, LLC - IL | 7136 | LEMONT | IL |
Source: NANPA Thousands Block Assignment Report (All Regions, Public), file date 09/20/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.