Area Code Studies & Data Analysis
Data-driven analysis of US area codes. Explore exhaustion rankings, demographic statistics, and more — all based on official NANPA and Census data.
Area Code Exhaustion Rankings
Which US area codes are running out of prefixes the fastest? Explore utilization data from NANPA for all 372 area codes.
144 area codes above 95% utilization
Richest & Densest Area Codes
Income and population density rankings for US area codes, based on Census ACS 5-year estimates.
233 US area codes ranked
Area Code Longevity
How long do area codes wait between assignment and activation? Analysis of all 372 in-service US area codes showing the gap between NANPA assignment and actual in-service dates.
372 codes analyzed — some waited 26+ years
Geographic Fragmentation
How far do area codes reach? County coverage analysis revealing which codes span the most territory and how fragmentation correlates with population density.
326 area codes mapped across US counties
Family Tree Complexity
Which area code families are the most complex? Analysis of 375 codes across 79 root families — size, depth, overlays, and split chains.
79 root families analyzed
Why these studies are different
Every figure here is computed at build time from one canonical database — NANPA's official numbering report, FCC filings, and U.S. Census ACS estimates. Nothing is hand-written: when NANPA publishes new relief data, every number below and inside each study updates automatically.
The dataset tracks 375 US area codes — from the 77 codes originally designated in 1947 to the 372 in service today — including 156 geographic splits and 137 overlays introduced through relief planning.
The numbering landscape in numbers
How the data stays current
NANPA's official report is ingested every five days, and a weekly reconciliation pass refreshes every derived statistic across the site. Study datasets are stamped with their real generation date — never a build timestamp. The public methodology and every upstream source are documented on Data Sources, and the aggregate view lives on Statistics.