Data Sources
Every data point on AreaCodeCentral is sourced from a public, verifiable primary source. We publish them all here — no black boxes.
The official administrator of the NANP. We use NANPA's public area code assignments, prefix (NXX) database, and code-exhaustion projections.
nationalnanpa.comWe use the FCC's public number-pooling data to estimate carrier market share per area code, plus FCC complaint data to flag high-risk codes.
fcc.govAll US county and city population figures come from the 2022 American Community Survey 5-year estimates — the most recent available as of 2024. The legacy area code directories still show 2010 Census data, which is up to 16 years stale.
census.gov/data/developers/data-sets/acs-5yearCanadian province and territory populations use Statistics Canada's 2023 quarterly demographic estimates, the most current available.
statcan.gc.caInternational country calling codes are assigned by the ITU-T (International Telecommunication Union — Telecommunication Standardization Sector) under the E.164 standard. We curate a list of 70+ major countries from this public database.
itu.int/rec/T-REC-E.164Area code coverage maps use OpenStreetMap tiles, licensed under the Open Database License (ODbL). Attribution is shown in the map embed. No API key required — OSM is fully open.
openstreetmap.orgCanadian area code assignments and prefix data come from the CNA, which administers the NANP within Canada.
cnac.caData refresh schedule
We refresh our area code dataset from NANPA quarterly (every 3 months) to pick up any new code activations or overlays. Population figures are refreshed annually, after the Census Bureau releases new ACS estimates each December. If you spot outdated data, please let us know — we typically fix verified errors within 48 hours.
License & attribution
Our curated datasets (the TypeScript files in src/data/) are available for reuse under the MIT license. The underlying source data remains under each provider's respective license (public domain for US government data; ODbL for OpenStreetMap). If you use our data in a public project, please credit "AreaCodeCentral.com" with a visible link.
Known limitations
- Number portability: Because of LNP, an area code no longer guarantees the caller's current physical location. Our data shows the original assignment, not the current carrier or location.
- Carrier market share: Estimated from FCC number-pooling data; may not reflect exact current allocations.
- Spam risk: Based on historical complaint data and known scam patterns. Even "low risk" codes can be spoofed.
- Prefix-level detail: Sample prefixes shown on each area code page are a subset of the full NANPA prefix database. For complete prefix data, query NANPA directly.