NumberResearchRecent prefix assignments
0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/20/2026
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 |
|---|---|---|---|---|---|---|
| 2018-08-16 | 661-439 | 0–9 XXXall 10 · 3 holders which blocks → | METROPCS, INC. | 5562 | BKFD MAIN | CA |
| 2015-07-28 | 661-563 | 0–9 XXXall 10 · 3 holders which blocks → | METROPCS, INC. | 5562 | BKFD MAIN | CA |
| 2015-04-13 | 661-490 | 0–9 XXXall 10 · 3 holders which blocks → | METROPCS, INC. | 5562 | BKFD MAIN | CA |
| 2014-12-24 | 661-497 | 0–9 XXXall 10 · 2 holders which blocks → | METROPCS, INC. | 5562 | BKFD MAIN | CA |
| 2014-04-18 | 661-440 | 0–9 XXXall 10 · 3 holders which blocks → | METROPCS, INC. | 5562 | BKFD MAIN | CA |
| 2012-08-28 | 661-437 | 0–9 XXXall 10 · 6 holders which blocks → | METROPCS, INC. | 5562 | BKFD MAIN | CA |
| 2007-04-12 | 661-346 | 0–9 XXXwhole prefix which blocks → | METROPCS, INC. | 5562 | BKFD MAIN | CA |
| 2002-02-11 | 661-213 | 0XXX3XXX4XXX5XXX8XXX9XXX · 5 holders which blocks → | METROPCS, INC. | 5562 | BKFD NORTH | CA |
| 2001-09-28 | 661-717 | 2XXX3XXX5XXX7XXX8XXX · 2 holders which blocks → | METROPCS, INC. | 5562 | BKFD MAIN | CA |
| 2001-05-21 | 661-343 | 4XXX5XXX8XXX9XXX · 2 holders which blocks → | METROPCS, INC. | 5562 | BKFD MAIN | CA |
| — | 661-344 | 1XXX3XXX4XXX5XXX7XXX8XXX9XXX · 3 holders which blocks → | METROPCS, INC. | 5562 | EARLIMART | CA |
| — | 661-427 | 1XXX3XXX4XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → | METROPCS, INC. | 5562 | BKFD MAIN | CA |
| — | 661-577 | 0XXX1XXX3XXX4XXX5XXX8XXX9XXX · 5 holders which blocks → | METROPCS, INC. | 5562 | TAFT | CA |
| — | 661-667 | 2XXX4XXX5XXX8XXX9XXX · 3 holders which blocks → | METROPCS, INC. | 5562 | MCFARLAND | CA |
| — | 661-759 | 0XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 4 holders which blocks → | METROPCS, INC. | 5562 | WASCO | CA |
| — | 661-900 | none assigned yet which blocks → | METROPCS, INC. | 5562 | BKFD MAIN | CA |
| — | 661-978 | none assigned yet which blocks → | METROPCS, INC. | 5562 | BKFD MAIN | CA |
| — | 661-979 | 4XXX which blocks → | METROPCS, INC. | 5562 | BKFD MAIN | CA |
Source: NANPA CO Code Assignments (Utilized, All States, Public), file date 09/20/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.