NumberResearchThousands-blocks in 307-223
This prefix’s ten 1,000-number blocks and who holds each — 10 on record · from the daily NANPA thousands-block report, 09/19/2026
The ten 1,000-number thousand-blocks inside prefix 307-223 and who was initially assigned each. Under pooling these blocks often belong to different carriers — the single prefix-level “assignee” is usually just the pool / code holder, not who holds the numbers. ← all 307 blocks
Most active assignees, all time — NPA 307
New assignments by month
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Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| — | 307-223-0XXX | 0000–0999 | Reserved | LEVEL 3 COMMUNICATIONS, LLC - WY | 9416 | LARAMIE | WY |
| 2010-01-22 | 307-223-1XXX | 1000–1999 | Assigned | BANDWIDTH.COM CLEC, LLC - WY | 081F | LARAMIE | WY |
| 2010-12-08 | 307-223-2XXX | 2000–2999 | Assigned | BANDWIDTH.COM CLEC, LLC - WY | 081F | LARAMIE | WY |
| 2010-07-02 | 307-223-3XXX | 3000–3999 | Assigned | MCIMETRO ACCESS TRANSMISSION SERVICES LLC | 7229 | LARAMIE | WY |
| — | 307-223-4XXX | 4000–4999 | Reserved | LEVEL 3 COMMUNICATIONS, LLC - WY | 9416 | LARAMIE | WY |
| 2011-03-09 | 307-223-5XXX | 5000–5999 | Assigned | BANDWIDTH.COM CLEC, LLC - WY | 081F | LARAMIE | WY |
| 2010-10-18 | 307-223-6XXX | 6000–6999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC | 6010 | LARAMIE | WY |
| 2011-03-17 | 307-223-7XXX | 7000–7999 | Assigned | ONVOY, LLC - WY | 450F | LARAMIE | WY |
| 2012-11-13 | 307-223-8XXX | 8000–8999 | Assigned | ONVOY, LLC - WY | 450F | LARAMIE | WY |
| 2012-11-13 | 307-223-9XXX | 9000–9999 | Assigned | ONVOY, LLC - WY | 450F | LARAMIE | WY |
Source: NANPA Thousands Block Assignment Report (All Regions, Public), file date 09/19/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.