Numbering activity brief — week ending September 28, 2026

The week in North American numbering, computed from the official NANPA files we ingest daily. All figures are initial-assignment records — not current-carrier data — and every number below can be recomputed from the sources on our change log.

The week in numbers

• 856 thousands-blocks assigned (down 33% week-over-week)
• 71 full prefixes (NXX) assigned (down 32% week-over-week)
• Change ledger: 5,556 field changed · 590 observed added · 48 observed removed

Most active assignees (blocks, 7 days)

Initial assignees under number pooling; state-suffixed entries of the same company are listed separately as they appear in the source.

Busiest area codes (blocks, 7 days)

• 820 — 37 blocks
• 458 — 21 blocks
• 657 — 20 blocks
• 603 — 19 blocks
• 681 — 18 blocks

Pool-pressure watch

Area codes whose available thousands-block inventory is thinnest relative to their own last-90-day consumption. The pool replenishes when new prefixes open, so this is a pressure signal, not a countdown:

Returned prefixes

Prefixes that left the assignment file this week (returns are unusual and worth watching): 229-203, 229-470, 229-478, 229-678, 229-706, 229-770, 229-912, 357-200.

New planning letters

• PL-638 — Assigning from NPA 543 for Non-Geographic Services
  npas affected: 500", "521", "522", "523", "524", "525", "526", "527", "528", "529", "532", "533", "538", "542", "543", "544", "566", "577", "588 · relief type: other

Sources: NANPA CO-code, thousands-block and planning-letter files retrieved daily (Tier A primary sources); figures recomputed on every import. Assignment records show initial assignees — because of number portability they do not identify the current serving carrier of any individual number. See methodology.