How to Look Up an Area Code: Where a Number Is From and What It Can't Tell You

To look up an area code, type the three digits, or the whole phone number, into an area code lookup. In a North American number the area code is the first three digits after the country code +1: in (512) 555-0123 it is 512, which is Texas, centred on Austin. The area code lookup returns the state or province, the largest cities, the time zone and any overlay codes. You can also type a state or a city to list the codes that serve it. It can't tell you the carrier or the line type.

Step 1: type what you have

You don't need to know the format. The tool accepts:

• a three-digit area code, such as 437
• a full phone number in any common format: +1, dots, brackets or dashes
• a US state or Canadian province, as a name or abbreviation, such as TX or ON
• a city name

Press Look up.

Step 2: read the result

For a code you get the location, its largest rate centers (or exchange areas in Canada), the time zone, overlay codes and when the code went into service. Each code links to its own page, such as area code 212, with local time, dialling examples and the full list of its largest rate centers. The full list of area codes is grouped by state, province and country.

A rate center is the local billing area a prefix belongs to, usually named after its main town. The tool lists a code's 12 largest by number of prefixes, which is a good guide to where its numbers are, though not a map of its boundary.

Find every area code in a state or city

Type the state or province and you get every area code in service there. Texas has 29. Type a city and the tool finds the codes whose largest rate centers carry that name, so Toronto returns 416, 437, 647 and 942.

Cities usually have more than one code because of overlays. When a code is close to running out of numbers, the North American Numbering Plan Administrator (NANPA) adds a new code over the same area instead of splitting it, and new numbers there can get either code. That is why two neighbours can have different area codes. The administrator tracks this code by code in its NPA reports.

Overlays are also why most of the US and Canada dial ten digits for local calls: with two codes in one area, seven digits no longer identify a number.

Step 3: look up a whole list

If you have a spreadsheet of numbers, switch to "A list of numbers" and paste them one per line, or upload a CSV. The phone column is found automatically. Download the CSV with area code, location, country, time zone, overlays and the largest rate centers added to every line.

That is useful before a calling or texting block:

• Group by time zone so you call people in their working hours. The calling hours checker covers legal calling windows, and the area code time zone tool is a quick reference.
• Spot Caribbean codes such as 876 (Jamaica). They share +1 with the US and Canada but are other countries, with different calling costs and texting rules. See how to check a missed call for a one-ring scam.
• Spot toll-free codes like 800 and 833, which have no location. See toll-free numbers.

Where the data comes from

The tool reads the numbering administrators' own files. Location, overlays, in-service date and dialling plan come from NANPA's NPA database. Cities come from the prefix files: NANPA's central office code assignments for the US, and the Canadian Numbering Administrator's CO code status file for Canada. Time zones follow the IANA Time Zone Database. Each code's page shows the date of the data, which is refreshed monthly.

What an area code can't tell you

This is the part people get wrong, so plainly:

• It's where the number was issued, not where the person is. People keep mobile numbers when they move.
• It can't tell you if a number is a mobile, landline or VoIP line. All three share area codes in North America. For that, you need a carrier lookup. See is this a cell phone number? and phone carrier lookup.
• It can't tell you whether a number is in service, or who owns it.
• City search covers each code's 12 largest rate centers, so a small town may not appear even though its numbers use the code.
• Caribbean and Atlantic codes have no public prefix file, so only the country and time zone are shown for them.

Question	Area code lookup	Carrier lookup
Where the number was issued	Yes	Usually
Time zone and overlays	Yes	Rarely
Mobile, landline or VoIP	No	Yes
Current carrier	No	Yes, after porting

Clean the numbers before you use the location

Locations are only as good as the numbers. A list with typos, missing digits and duplicates will produce confident-looking nonsense. Normalise to E.164 first (see US phone number format and E.164 phone number format), then validate. The US phone number checker and the phone number validator handle one number or a list.

Look up your own area code

Open the area code lookup and type a code, a number, a state or a city. For a list of numbers you plan to call or text, upload it on the verify page: every number comes back with its E.164 form, country and type, and nothing is dialled or texted. Live carrier lookups for US and Canadian numbers, which add the real line type and carrier, are a paid extra; see pricing.