NumberResearch Membership · Data 09/20/2026

Recent prefix assignments

0 prefixes assigned in the last 30 days · from the daily NANPA CO code file, 09/20/2026

Full prefixes (NXX) Thousands-blocks (1,000-number pools)

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.

Most active assignees, all time — NPA 956
SOUTHWESTERN BELL 145
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
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Recent NPA-NXX prefix assignments
AssignedNPA-NXXThousands-blocks taken (last-4 opening)Code holderOCNRate centerState
— 956-723 not yet reported which blocks → SOUTHWESTERN BELL 9533 LAREDO TX
— 956-724 not yet reported which blocks → SOUTHWESTERN BELL 9533 LAREDO TX
— 956-725 not yet reported which blocks → SOUTHWESTERN BELL 9533 LAREDO TX
— 956-726 not yet reported which blocks → SOUTHWESTERN BELL 9533 LAREDO TX
— 956-727 not yet reported which blocks → SOUTHWESTERN BELL 9533 LAREDO TX
— 956-728 not yet reported which blocks → SOUTHWESTERN BELL 9533 LAREDO TX
— 956-729 not yet reported which blocks → SOUTHWESTERN BELL 9533 LAREDO TX
— 956-730 0XXX1XXX2XXX3XXX4XXX6XXX7XXX8XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 HARLINGEN TX
— 956-748 0XXX5XXX6XXX7XXX8XXX · 5 holders which blocks → SOUTHWESTERN BELL 9533 RIO HONDO TX
— 956-752 1XXX2XXX3XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 HARLINGEN TX
— 956-753 not yet reported which blocks → SOUTHWESTERN BELL 9533 LAREDO TX
— 956-755 1XXX3XXX4XXX5XXX6XXX7XXX8XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 BROWNSVL TX
— 956-760 not yet reported which blocks → SOUTHWESTERN BELL 9533 HARLINGEN TX
— 956-761 9XXX which blocks → SOUTHWESTERN BELL 9533 PORTISABEL TX
— 956-764 0XXX9XXX which blocks → SOUTHWESTERN BELL 9533 LAREDO TX
— 956-765 0XXX2XXX7XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 ZAPATA TX
— 956-772 0XXX2XXX3XXX4XXX5XXX7XXX8XXX · 6 holders which blocks → SOUTHWESTERN BELL 9533 PORTISABEL TX
— 956-781 not yet reported which blocks → SOUTHWESTERN BELL 9533 PHARR TX
— 956-782 6XXX which blocks → SOUTHWESTERN BELL 9533 PHARR TX
— 956-783 not yet reported which blocks → SOUTHWESTERN BELL 9533 PHARR TX
— 956-784 0XXX1XXX2XXX4XXX5XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 PHARR TX
— 956-787 not yet reported which blocks → SOUTHWESTERN BELL 9533 PHARR TX
— 956-790 0XXX8XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 LAREDO TX
— 956-791 not yet reported which blocks → SOUTHWESTERN BELL 9533 LAREDO TX
— 956-794 0XXX which blocks → SOUTHWESTERN BELL 9533 LAREDO TX
— 956-795 not yet reported which blocks → SOUTHWESTERN BELL 9533 LAREDO TX
— 956-796 not yet reported which blocks → SOUTHWESTERN BELL 9533 LAREDO TX
— 956-825 0XXX1XXX2XXX3XXX4XXX6XXX8XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 MERCEDES TX
— 956-831 not yet reported which blocks → SOUTHWESTERN BELL 9533 BROWNSVL TX
— 956-832 2XXX3XXX4XXX5XXX7XXX8XXX9XXX · 3 holders which blocks → SOUTHWESTERN BELL 9533 BROWNSVL TX
— 956-838 9XXX which blocks → SOUTHWESTERN BELL 9533 BROWNSVL TX
— 956-843 0XXX which blocks → SOUTHWESTERN BELL 9533 MCALLEN TX
— 956-848 0XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 7 holders which blocks → SOUTHWESTERN BELL 9533 FALCON HTS TX
— 956-926 9XXX which blocks → SOUTHWESTERN BELL 9533 MCALLEN TX
— 956-928 9XXX which blocks → SOUTHWESTERN BELL 9533 MCALLEN TX
— 956-943 8XXX9XXX · 2 holders which blocks → SOUTHWESTERN BELL 9533 PORTISABEL TX
— 956-948 0XXX2XXX3XXX4XXX6XXX7XXX8XXX9XXX · 5 holders which blocks → SOUTHWESTERN BELL 9533 ENCINAL TX
— 956-971 7XXX which blocks → SOUTHWESTERN BELL 9533 MCALLEN TX
— 956-972 not yet reported which blocks → SOUTHWESTERN BELL 9533 MCALLEN TX
— 956-982 not yet reported which blocks → SOUTHWESTERN BELL 9533 BROWNSVL TX
— 956-983 0XXX2XXX3XXX8XXX9XXX · 4 holders which blocks → SOUTHWESTERN BELL 9533 BROWNSVL TX
— 956-984 8XXX9XXX which blocks → SOUTHWESTERN BELL 9533 MCALLEN TX
— 956-986 1XXX which blocks → SOUTHWESTERN BELL 9533 BROWNSVL TX
— 956-992 1XXX which blocks → SOUTHWESTERN BELL 9533 MCALLEN TX
— 956-994 not yet reported which blocks → SOUTHWESTERN BELL 9533 MCALLEN 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.