NumberResearchThousands-blocks in 412-503
This prefix’s ten 1,000-number blocks and who holds each — 10 on record · from the daily NANPA thousands-block report, 09/20/2026
The ten 1,000-number thousand-blocks inside prefix 412-503 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 412 blocks
Most active assignees, all time — NPA 412
New assignments by month
Sep 2026
Aug 2026
Jul 2026
Jun 2026
May 2026
Apr 2026
Mar 2026
Feb 2026
Jan 2026
Dec 2025
Nov 2025
Oct 2025
| Assigned | Thousands-block | Last 4 digits | Status | Assignee | OCN | Rate center | State |
|---|---|---|---|---|---|---|---|
| 2017-12-13 | 412-503-0XXX | 0000–0999 | Assigned | IP HORIZON LLC | 515J | PTTSBGZON7 | PA |
| 2017-12-13 | 412-503-1XXX | 1000–1999 | Assigned | IP HORIZON LLC | 515J | PTTSBGZON7 | PA |
| 2014-11-25 | 412-503-2XXX | 2000–2999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | PTTSBGZON7 | PA |
| 2014-11-25 | 412-503-3XXX | 3000–3999 | Assigned | NEW CINGULAR WIRELESS PCS, LLC - IL | 6534 | PTTSBGZON7 | PA |
| — | 412-503-4XXX | 4000–4999 | Reserved | MCIMETRO ACCESS TRANSMISSION SERVICES LLC | 7229 | PTTSBGZON7 | PA |
| 2015-04-22 | 412-503-5XXX | 5000–5999 | Assigned | METROPCS, INC. | 5562 | PTTSBGZON7 | PA |
| — | 412-503-6XXX | 6000–6999 | Available | PTTSBGZON7 | PA | ||
| 2016-06-21 | 412-503-7XXX | 7000–7999 | Assigned | BANDWIDTH.COM CLEC, LLC - PA | 002F | PTTSBGZON7 | PA |
| 2025-04-15 | 412-503-8XXX | 8000–8999 | Assigned | ONVOY, LLC - PA | 547E | PTTSBGZON7 | PA |
| — | 412-503-9XXX | 9000–9999 | Reserved | MCIMETRO ACCESS TRANSMISSION SERVICES LLC | 7229 | PTTSBGZON7 | PA |
Source: NANPA Thousands Block Assignment Report (All Regions, Public), file date 09/20/2026 — Tier A primary source, refreshed on every import. Viewing is free; bulk downloads require a membership.