Recent prefix assignments
0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/19/2026
The Code holder is who opened each NPA-NXX prefix — not necessarily who holds the numbers. A prefix is 10,000 numbers, but under pooling its ten 1,000-number blocks are handed out individually, often to different carriers; the code holder may hold only one block, or none. The Thousands-blocks column shows how the ten blocks are really split — click which blocks → to see who holds each 1,000-number block and its last-4-digit range. Assignments are initial assignments; the current serving carrier may differ due to portability.
| Assigned | NPA-NXX | Thousands-blocks taken (last-4 opening) | Code holder | OCN | Rate center | State |
|---|---|---|---|---|---|---|
| 2006-09-13 | 240-595 | 0–9 XXXall 10 · 3 holders which blocks → | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD | 6395 | WSHNGTNZN3 | MD |
| 2006-08-09 | 240-577 | 0–9 XXXall 10 · 3 holders which blocks → | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD | 6395 | LEONARDTN | MD |
| 2006-08-08 | 240-512 | 0–9 XXXall 10 · 6 holders which blocks → | CORE COMMUNICATIONS, INC.- MD | 2593 | WSNG238Z13 | MD |
| 2006-07-25 | 240-543 | 0–9 XXXwhole prefix which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | WSHNGTNZN2 | MD |
| 2006-07-12 | 240-567 | 0–9 XXXwhole prefix which blocks → | VERIZON MARYLAND, INC. | 9212 | WSNGTNZN10 | MD |
| 2006-06-12 | 240-357 | 0–9 XXXall 10 · 2 holders which blocks → | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD | 6395 | FREDERICK | MD |
| 2006-06-12 | 240-688 | 0–9 XXXall 10 · 2 holders which blocks → | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD | 6395 | WSHNGTNZN3 | MD |
| 2006-05-19 | 240-654 | 0–9 XXXall 10 · 4 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | GAITHERSBG | MD |
| 2006-03-29 | 240-520 | 0–9 XXXall 10 · 3 holders which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | HAGERSTOWN | MD |
| 2006-03-09 | 240-345 | 0–9 XXXall 10 · 5 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - MD | 6119 | ASHTON238 | MD |
| 2006-01-05 | 240-755 | 0–9 XXXall 10 · 4 holders which blocks → | COMCAST IP PHONE, LLC | 318J | LAUREL238 | MD |
| 2005-12-30 | 240-565 | 0–9 XXXall 10 · 4 holders which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | LAUREL238 | MD |
| 2005-12-30 | 240-575 | 0–9 XXXall 10 · 6 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - MD | 6119 | FREDERICK | MD |
| 2005-05-27 | 240-821 | 0–9 XXXall 10 · 4 holders which blocks → | PAETEC ITEL, LLC | 829J | WSHNGTNZN3 | MD |
| 2005-05-20 | 240-477 | 0–9 XXXall 10 · 3 holders which blocks → | PAETEC ITEL, LLC | 829J | GAITHERSBG | MD |
| 2005-05-06 | 240-750 | 0–9 XXXall 10 · 3 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | GAITHERSBG | MD |
| 2005-04-22 | 240-454 | 0–9 XXXall 10 · 5 holders which blocks → | PAETEC ITEL, LLC | 829J | GAITHERSBG | MD |
| 2004-12-13 | 240-394 | 0–9 XXXall 10 · 4 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | MOUNT AIRY | MD |
| 2004-11-22 | 240-770 | 0–9 XXXall 10 · 3 holders which blocks → | COMCAST IP PHONE, LLC | 318J | WSHNGTNZN4 | MD |
| 2004-11-01 | 240-284 | 0–9 XXXall 10 · 5 holders which blocks → | LEVEL 3 COMMUNICATIONS, LLC - MD | 6119 | FROSTBURG | MD |
| 2004-11-01 | 240-288 | 0–9 XXXall 10 · 6 holders which blocks → | COMCAST IP PHONE, LLC | 318J | THURMONT | MD |
| 2004-07-27 | 240-405 | 0–9 XXXall 10 · 4 holders which blocks → | PAETEC ITEL, LLC | 829J | FREDERICK | MD |
| 2004-07-27 | 240-478 | 0–9 XXXall 10 · 4 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | WSHNGTNZN3 | MD |
| 2004-05-04 | 240-276 | 0–9 XXXwhole prefix which blocks → | VERIZON MARYLAND, INC. | 9212 | WSNGTNZN10 | MD |
| 2003-10-30 | 240-681 | 0XXX1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → | PAETEC ITEL, LLC | 829J | BRANDYWINE | MD |
| 2003-07-23 | 240-205 | 0–9 XXXall 10 · 3 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | WSNGTNZN10 | MD |
| 2003-03-27 | 240-307 | 0–9 XXXall 10 · 6 holders which blocks → | BANDWIDTH.COM CLEC, LLC - MD | 071F | EMMITSBURG | MD |
| 2002-11-04 | 240-388 | 0–9 XXXall 10 · 3 holders which blocks → | METROPCS, INC. | 5562 | GAITHERSBG | MD |
| 2002-10-18 | 240-277 | none assigned yet which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | WSHNGTNZN2 | MD |
| 2002-10-18 | 240-367 | 0XXX1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 3 holders which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | FREDERICK | MD |
| 2002-10-15 | 240-291 | 0–9 XXXall 10 · 2 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | HAGERSTOWN | MD |
| 2002-10-15 | 240-344 | 0–9 XXXwhole prefix which blocks → | NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | FREDERICK | MD |
| 2002-09-17 | 240-286 | 0–9 XXXall 10 · 2 holders which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | WSHNGTNZN2 | MD |
| 2002-07-03 | 240-304 | 0–9 XXXall 10 · 3 holders which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | WSHNGTNZN5 | MD |
| 2002-07-03 | 240-398 | 0XXX1XXX2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 4 holders which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | WSHNGTNZN3 | MD |
| 2002-06-11 | 240-566 | 0–9 XXXall 10 · 7 holders which blocks → | VERIZON MARYLAND, INC. | 9212 | FREDERICK | MD |
| 2002-05-16 | 240-643 | 1XXX2XXX3XXX4XXX5XXX7XXX8XXX which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | WSHNGTNZN3 | MD |
| 2002-05-15 | 240-422 | 1XXX2XXX3XXX4XXX5XXX7XXX8XXX · 2 holders which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | FREDERICK | MD |
| 2002-01-09 | 240-506 | 7XXX8XXX9XXX which blocks → | NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | WSNGTNZN10 | MD |
| 2001-12-12 | 240-522 | 0XXX1XXX2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 4 holders which blocks → | METROPCS, INC. | 5562 | CUMBERLAND | MD |
| 2001-11-12 | 240-418 | none assigned yet which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | WSHNGTNZN2 | MD |
| 2001-10-31 | 240-505 | not yet reported which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | WSHNGTNZN3 | MD |
| 2001-10-25 | 240-426 | none assigned yet which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | WSHNGTNZN2 | MD |
| 2001-10-08 | 240-501 | none assigned yet which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | WSHNGTNZN3 | MD |
| 2001-08-09 | 240-446 | 5XXX7XXX8XXX which blocks → | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD | 6395 | FREDERICK | MD |
| 2001-08-09 | 240-925 | 7XXX which blocks → | CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD | 6395 | LEONARDTN | MD |
| 2001-07-10 | 240-466 | 0–9 XXXall 10 · 7 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | MECHANCSVL | MD |
| 2001-06-20 | 240-455 | 2XXX3XXX4XXX5XXX6XXX7XXX8XXX · 3 holders which blocks → | PAETEC ITEL, LLC | 829J | WSHNGTNZN5 | MD |
| 2001-06-20 | 240-515 | 0–9 XXXall 10 · 2 holders which blocks → | NEW CINGULAR WIRELESS PCS, LLC - DC | 4036 | WSHNGTNZN2 | MD |
| 2001-06-14 | 240-580 | 1XXX2XXX3XXX4XXX5XXX8XXX9XXX · 3 holders which blocks → | OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC | 6855 | CUMBERLAND | MD |
Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/19/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.