Korean Phone Number Format: 010, Area Codes and the +82 Country Code

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A Korean phone number tells you a lot before you dial it. The first two or three digits say whether you are calling a mobile, a landline in a particular city, an internet phone, a toll-free line or a relay number that hides somebody’s real number. Once you can read that prefix, the rest of the format is easy, including the one change you need to make when you write the number for someone outside Korea.

This guide works through the format from the front of the number to the back. The numbering facts come from the published Korean numbering plan as summarized in Wikipedia’s article on Korean telephone numbers, and the emergency numbers from the UK government’s travel advice for South Korea. To see how software handles these numbers, I also ran a set of sample numbers through libphonenumber-js (version 1.13.15), a JavaScript port of the phone number library Google maintains. Those results are in the last section, because a couple of them surprised me.

Step 1: Read the first digits

Almost every Korean number you see written down starts with 0. That 0 is the trunk prefix, used for calls inside Korea. The digits right after it tell you what kind of line it is.

The mobile row is the one you will use most. Starting in 2004, new Korean mobile numbers moved to the single 010 prefix, replacing the older carrier prefixes 011, 016, 017, 018 and 019. So a modern Korean mobile number is eleven digits written 010, four digits, four digits.

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Step 2: Know when the area code can be dropped

Korea uses an open dialing plan. Calling a landline from another landline in the same area, you can leave the area code off, so 02-312-3456 is just 312-3456 from inside Seoul. From a mobile phone you always include the area code. Most foreigners call from a mobile, so the practical rule is simple: dial the number exactly as written, hyphens aside.

The eight-digit business numbers starting 1588, 1577, 1566 and similar are different. They have no area code and route to a company’s call center wherever it is. Wikipedia’s summary of the numbering plan notes that some of them cannot be dialed from abroad. Check before relying on one from overseas.

Step 3: Drop the 0 when you add +82

This is the step people get wrong. Korea’s country code is +82, and when you add it you remove the leading 0 of the domestic number.

Use the +82 form whenever the number will be read or dialed from outside Korea: an overseas bank, an airline booking, a visa form, a friend saving your number at home. Inside Korea, people write and expect the 010 form.

Step 4: Learn the short numbers that have no prefix at all

Emergency and help lines are three or four digits and dialed as they are. The UK government’s travel advice lists 112 for police and 119 for fire and ambulance. The same page describes 1330, the Korea Tourism Organization’s travel hotline, as offering help in several languages including English from 7am to midnight, with three-way interpretation to emergency services. It also lists the Danuri call center, 1577-1366, as available around the clock.

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Save 1330 in your phone before you need it. In an emergency it is far easier to have the number than to look it up.

What software makes of Korean numbers

Phone fields on websites usually run numbers through a library like the one I tested. Three of the results stood out.

• It quietly fixed a common mistake. I typed +82 010 1234 5678, keeping the 0 that should have been dropped. The library treated it as valid and normalized it to +821012345678. A well-built form will do the same, but I would not count on every form being well built. Drop the 0 yourself.
• It accepted an old prefix. A sample 011 number came back as a valid mobile number. That only means the digits fit the pattern. No format check can tell you whether a number is actually in service.
• It grouped a 050 number differently. The sample 0505-123-4567 came back formatted as 050-5123-4567. Same digits, different hyphens. If a number on a receipt or delivery app looks oddly split, the digits are what matter.

Mobile, Seoul and Busan landlines, the 070 internet number, the 080 toll-free number and the 1588 business number all parsed as valid and got the types you would expect.

Why a Korean number matters beyond calls

A Korean mobile number in your own name is often what gets you into Korean websites and apps, because sign-ups and payments verify you by phone. That is the hurdle covered in our guide to Korean identity verification for foreigners. And if you are filling in Korean forms anyway, the address field has its own conventions, explained in how to write a Korean address in English.

Common questions about Korean numbers

How many digits is a Korean mobile number?

Eleven in the domestic form, starting 010. With the country code it is +82 followed by ten digits.

Is it +82 10 or +82 010?

+82 10. The leading 0 is only for calls inside Korea and is dropped after the country code.

What is the area code for Seoul?

02 inside Korea, or 2 after +82 from abroad.

Why did I get a call from a 070 number?

070 is an internet phone line. It is a legitimate number type used by businesses and individuals, so the prefix alone does not tell you whether the call is wanted.

Prefixes, dates and dialing rules are as summarized in Wikipedia’s article on telephone numbers in South Korea. Emergency numbers and hotline hours are from the UK government’s foreign travel advice for South Korea. The software results come from my own run of libphonenumber-js 1.13.15 on sample numbers; all numbers shown are samples, not real subscribers.