DialWick · Number Directory
US area code lookup — where a phone number is really from
Free area code lookup for the US and Canada, plus ZIP code lists, county guides, and international dialing formats — with the split-and-overlay history and local context a one-line answer leaves out.
Look up an area code
Type a three-digit area code or paste a US/Canada phone number — for example 212 or (415) 555-0100. DialWick reads the NANP prefix from your input using NANPA-derived registry data; it does not identify the caller or confirm the line is still active.
Toll-free codes (800, 888, 877, …) and geographic codes both work. This is not reverse phone lookup.
Need the full index? Area code lookup on the hub page Browse all guides
What this directory covers
Most lookup sites stop at a city name. DialWick keeps the registry row and the story around it: when a code was created, what it split from, and which guides on this site go deeper.
Area code overlays and split history
Overlays, exhaust dates, and retired boundaries are why a prefix alone is ambiguous. Start with how area codes work, then open a state list such as California area codes.
ZIP code lookup by city
For shipping labels and forms, use city ZIP code lists with county columns — mail routes, not phone geography.
International dialing from the US
Country codes, exit codes, and mobile-prefix quirks live under international dialing — separate from NANP area code lookup.
Area code lookup FAQ
How do I look up an area code from a phone number?
Use the first three digits after the country code (+1). On a US number like (415) 555-0100, the area code is 415. DialWick's lookup above maps that prefix to its NANP assignment; it does not identify the caller or validate that the number is still in service.
What is an area code overlay?
An overlay adds a new area code on top of the same geography as an existing code, so two prefixes serve the same region. New numbers can get either code. Overlays replaced most geographic splits after the 1990s — see the how area codes work guide for examples.
Can ZIP code lookup tell me the same thing as an area code?
No. ZIP codes follow USPS delivery routes; area codes follow the telephone numbering plan. A single ZIP can span multiple area codes, and overlays mean one metro can issue several prefixes. Use ZIP code lookup by city for mail, and area code lookup for the phone prefix.
Are toll-free area codes (800, 888, 877) tied to a state?
No. Toll-free and other non-geographic codes are nationwide services in the NANP registry. A 800 number does not reveal where the caller is located — only which service class the prefix belongs to.
Area Codes
State and province lists, individual lookups, and how the numbering plan actually works.
ZIP Codes
City ZIP code lists and county breakdowns, sourced from USPS/Census data.
Counties
Which county a major US city actually sits in.
International Dialing
Current dialing formats for calling abroad from the US.