Getting a Korean Joint Certificate as a Foreigner: What…

Your bank app wants something called a certificate.

Not your ARC. Not your passport. A file.

You opened a Korean account, installed the bank app, and tried to send rent money. Then a pop-up asked for a gongdong injeungseo (joint certificate). Hometax showed the same button. So did Government24. Nobody at the branch explained what it was.

That’s a common wall. The fix is simpler than it looks, but the order matters. This guide covers how to issue the certificate, use it on Hometax, renew it before expiry, and move it to a new phone. It applies to D-2 and D-10 students, E-7 and F-2 workers, F-5 and F-6 residents, and F-4 overseas Koreans. If you don’t have your residence card yet, start there. ARC application Korea

Why does every Korean website keep asking for this certificate?

A joint certificate is a digital signature file that proves your identity when you log in or approve something online. Korean banks, the National Tax Service and Government24 all accept it. It replaced the old “accredited certificate” in December 2020. The bank-use version costs nothing, lasts one year, and works on most government sites you’ll need.

Before 2020, Korea used the gongin injeungseo (accredited certificate). For two decades, many sites effectively had to use it. The amended Electronic Signature Act removed that special status. Private options like PASS, Kakao and Naver authentication became equal alternatives. The old certificate kept working. It just got a new name.

The law states its goal plainly:

“The purpose of this Act is to ensure the security and reliability of electronic documents and promote their use by prescribing basic matters concerning electronic signatures.” (Electronic Signature Act, Article 1, English translation via MOLEG)

So why does it still matter? Banks and tax systems built their security around it. Many still require it for certain actions, even though simple login apps now cover the rest.

Who actually issues it

Four licensed certification authorities issue joint certificates:

• Korea Financial Telecommunications and Clearings Institute (KFTC), brand name yessign
• Korea Information Certificate Authority (KICA), brand name signGate
• KOSCOM, brand name SignKorea
• Korea Electronic Certification Authority, brand name CrossCert

You rarely deal with them directly. Your bank acts as the counter, and most banks issue through KFTC yessign. The Korea Internet & Security Agency serves as the accreditation body for electronic signature evaluation, under the Ministry of Science and ICT.

Bank-use or general-purpose?

For most foreign residents, the free bank-use certificate is enough. You’d only pay for general-purpose if you want a single certificate across banks, brokerages, insurers and public bidding sites.

Here’s the catch. You can’t create either one on your phone alone. Something has to be set up at the bank first, and that’s the next step.

What do you need before issuing it at a bank branch?

You can’t issue a joint certificate until your account has internet banking switched on. Turning it on usually takes one visit to a bank branch. Bring your ARC, your passport, and a phone plan in your own name. The bank gives you an OTP device or a security card. You’ll need its code later, so keep it safe.

ARC required documents

The foreign registration number on your oegugin deungnokjeung (Alien Registration Card, or ARC) is your identity key for the whole process. Banks run their real-name check against it.

Bring these:

1. Your ARC, the original card. A photo of it won’t work.
2. Your passport. Some branches use it to confirm your name spelling.
3. A phone registered under your ARC. Prepaid plans opened with only a passport often fail later checks.
4. Proof of purpose, if you’re opening a new account. Students can show an enrollment certificate. Workers can show an employment contract or employment certificate.
5. The 4-digit account PIN you set when you opened the account.

Just arrived with only a passport? You may be able to open a basic account, but online services usually stay locked. Apply for your ARC through HiKorea, the Korea Immigration Service portal. Come back once the card arrives.

What to say at the counter

Staff may not speak English. Show them this line: 인터넷뱅킹 신청하고 공동인증서 발급하려고요. It means “I want to sign up for internet banking and issue a joint certificate.”

New accounts often start as a hando jehan gyejwa (limited account) with a low daily transfer cap. That limit doesn’t stop you from issuing a certificate. It only limits how much money you can move.

Before you leave, ask one more question. Is your name on file exactly as it appears on your ARC? You’ll see why in a minute.

Why does the online issuing step fail for so many foreigners?

Issuing happens in the bank app or on the bank website, not at the counter. You enter your foreign registration number, account number, PIN and OTP code, then pass a phone check. Most failures come from two things. Either your phone plan isn’t in your name, or your name doesn’t match the bank’s record exactly, spaces included.

The steps look similar at every major bank:

1. Open the bank app and find the Certificate Center (injeung senteo).
2. Choose Joint Certificate, then Issue/Reissue.
3. Agree to the terms and enter your internet banking ID.
4. Enter your foreign registration number.
5. Enter your account number and 4-digit account PIN.
6. Enter the code from your OTP device or security card.
7. Complete phone verification by text message, the PASS app, or an ARS phone call.
8. Create a certificate password with at least 10 characters, mixing letters, numbers and special characters.
9. Choose where to save it: your phone, your PC, or a USB drive.

That’s it. On a good day it takes about five minutes.

Three errors that send people back to the branch

• Name mismatch. Your ARC might show “NGUYEN VAN AN” while the bank saved “NGUYENVANAN”. Verification compares your name across bank, ARC and carrier records. A missing space can be enough to fail.
• Phone not in your name. Identity verification links your ARC to your mobile carrier. A phone registered to your employer, spouse or friend won’t pass.
• Customer info still on your passport. If you opened the account before getting your ARC, the bank may still hold your passport number. Ask the branch to switch it to your foreign registration number.

One more warning. Nobody, including the bank, can recover your certificate password. Store it somewhere safe. Forget it, and you’ll have to reissue.

Now you have the file. The first place most people try it is Hometax. That’s where the second wall appears.

How do you log in to Hometax with your certificate?

On your first visit, you must register the certificate on Hometax before it works as a login. Open Hometax, choose joint certificate login, and register it with your foreign registration number. After that, the same certificate lets you handle year-end tax documents, print tax certificates and file income tax. Simple authentication apps work for most individual tasks too.

Hometax is the online service of the National Tax Service. You’ll use it for:

• Yeonmal jeongsan (year-end tax settlement), which salaried workers handle in January and February.
• Downloading deduction data for medical, card and insurance spending.
• Printing a tax payment certificate. Some visa applications, including certain F-2 and F-5 cases, ask for proof of tax payment.
• Filing comprehensive income tax in May if you have freelance or side income.

Hometax login certificate setup

1. Go to Hometax and select Login.
2. Choose the joint or financial certificate option (공동·금융인증서).
3. On your first visit, the site asks you to register the certificate. Enter your foreign registration number.
4. Select your certificate file and enter its password.
5. From then on, you just pick the certificate and type the password.

Renewed or reissued later, and Hometax rejects it? Run the certificate registration menu again. It takes under a minute.

The National Tax Service also publishes English guides for foreign taxpayers. Read one before January so the deadlines don’t surprise you. year-end tax settlement foreigner Korea

Do you even need the joint certificate here?

Not always. Hometax also accepts:

• The Financial Certificate (geumyung injeungseo), issued by KFTC through your bank. It’s stored in the cloud, uses a 6-digit PIN, and lasts three years.
• Ganpyeon injeung (simple authentication) through apps like Kakao, Naver, PASS and Toss.

Simple authentication is the easiest way to check your records. Still, the joint certificate wins in a few cases. It works on a PC with your phone in another room. It also works on older public sites and some business filings that don’t support every app.

All of this works for exactly one year. Then the clock runs out.

What happens when it expires or you switch phones?

A joint certificate lasts one year. You can renew it from 30 days before the expiry date until that date, usually in under a minute in your bank app. Miss that window and you must reissue it, repeating the OTP and phone checks. To move it to a new phone, use the export and import menu. Lost the old phone? Reissue.

Certificate renewal expiry: the 30-day window

Banks usually send a text reminder about a month before expiry. Renewal is quick:

1. Open the bank app and go to Certificate Center.
2. Choose Renew (gaengsin).
3. Select the certificate and enter its password.
4. Confirm. Your new expiry date is one year later.

Renewal is light because the current certificate proves who you are. Reissue isn’t. After expiry, you repeat everything: ID, account PIN, OTP code and phone verification. Bank-use reissue is still free. It’s just slower.

Set a phone reminder for 30 days before the date shown on your certificate. Two minutes now saves a branch trip later.

Move certificate to new phone

Your certificate lives on the device where you saved it. A new phone won’t have it automatically. There are two paths.

If you still have the old phone:

1. Install the same bank app on the new phone.
2. On the new phone, open Certificate Center and choose Import (gajyeogi). The app shows a one-time code.
3. On the old phone, choose Export (naebonaegi) and enter that code.
4. Enter the certificate password. The file copies across.

The same menu moves a certificate between a PC and a phone. On the bank website, choose the PC-to-smartphone option and follow the code prompts.

If the old phone is lost, broken or already reset, there’s nothing to copy. Reissue instead. Reissuing cancels the old certificate. That also protects you if the lost phone lands in someone else’s hands.

Export the certificate before any factory reset. The same goes for carrier changes. If you’re switching plans or moving the line into your own name, sort the phone first, then reissue. Korea phone plan foreigner ARC

So that’s the full cycle. What should you actually do this week?

What should you do this week to avoid getting locked out?

Check three things today. First, confirm your bank holds your foreign registration number, not your passport number. Second, make sure your phone plan is in your name. Third, find your certificate’s expiry date and set a reminder 30 days earlier. Those three checks prevent most of the branch trips foreigners make over this certificate.

Then work through this short list:

• Internet banking switched on, with an OTP device or security card in hand
• Bank-use joint certificate issued, password stored safely
• Certificate registered on Hometax before the January tax season
• A backup copy saved on a PC or USB drive
• Renewal reminder set on your phone

Use more than one bank? You don’t need a second certificate. Each bank has a menu for registering another institution’s certificate (tahaeng injeungseo deungnok). Do it once per bank, and the same file works everywhere.

Changing visas doesn’t reset any of this. Going from D-10 to E-7, or F-2 to F-5, keeps your foreign registration number. Your certificate keeps working until its own expiry date.