References
Sources & Data
Where our area code information comes from, and how to check the authoritative record yourself.
Area code data on this site is based on the public North American Numbering Plan. For official, real-time records we point you to the primary sources below.
Primary sources
- NANPA (North American Numbering Plan Administrator) — the official administrator that assigns area codes and publishes relief planning and activation schedules.
- Federal Communications Commission (FCC) — the U.S. regulator that sets numbering policy, including the 988 designation and the 2021 move to 10-digit dialing in areas that still used 7 digits.
- State public utility commissions — approve and announce splits and overlays within each state.
- SAMHSA & the Suicide and Crisis Lifeline — for details on the 988 service.
How we keep data current
Activation dates, overlay relationships and planned relief codes are synced from NANPA's public NPA report (latest file: 10/01/2026). We review them periodically and label time-sensitive pages with a last-updated date. New and planned codes are tracked on the newest area codes page.
Report a correction
If you find an error or an out-of-date detail, please contact us with the area code and the correction. Accuracy is the whole point of this site.