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 |
|---|---|---|---|---|---|---|
| — | 580-328 | not yet reported which blocks → | DOBSON TEL. CO. | 1988 | TALOGA | OK |
| — | 580-488 | not yet reported which blocks → | DOBSON TEL. CO. | 1988 | LEEDEY | OK |
| — | 580-497 | none assigned yet which blocks → | DOBSON TEL. CO. | 1988 | CHEYENNE | OK |
| — | 580-526 | not yet reported which blocks → | DOBSON TEL. CO. | 1988 | ERICK | OK |
| — | 580-534 | not yet reported which blocks → | DOBSON TEL. CO. | 1988 | SWEETWATER | OK |
| — | 580-655 | not yet reported which blocks → | DOBSON TEL. CO. | 1988 | REYDON | OK |
| — | 580-926 | not yet reported which blocks → | DOBSON TEL. CO. | 1988 | CAMARGO | OK |
| — | 580-983 | 5XXX which blocks → | DOBSON TEL. CO. | 1988 | ROGERMILLS | OK |
| — | 580-995 | not yet reported which blocks → | DOBSON TEL. CO. | 1988 | VICI | OK |
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.