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 |
|---|---|---|---|---|---|---|
| — | 281-266 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-267 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-268 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-349 | not yet reported which blocks → | SPOK, INC. | 6630 | HSTNSUBURB | TX |
| — | 281-418 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-439 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-472 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-510 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-527 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-551 | not yet reported which blocks → | SPOK, INC. | 6630 | BAMMEL | TX |
| — | 281-613 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-621 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-629 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-718 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-735 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-952 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-963 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
| — | 281-981 | not yet reported which blocks → | SPOK, INC. | 6630 | HOUSTON | TX |
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.