FAQ – eSIM

An eSIM is a digital SIM profile installed directly on a compatible smartphone.

You do not need to insert or replace a physical SIM card. After receiving the QR code, you can add the eSIM through your phone's settings.

Korea USIM provides three main types of eSIM products.

1. Travel Data eSIM

Travel Data eSIMs provide mobile data in Korea and other international destinations.

They normally do not include:

• A local phone number
• Standard voice calls
• Standard SMS

You can still use internet-based communication apps such as WhatsApp, LINE, KakaoTalk, FaceTime, and Messenger.

The available network, speed, data allowance, and validity period depend on the destination and selected product.

2. Official SKT Roaming Center eSIM

The official SKT eSIM provides mobile data in Korea.

Available phone number and calling services depend on the selected plan and customer eligibility.

• The 1-day plan is data-only.
• Eligible foreign-national customers may use a Korean phone number after the required passport verification.
• Eligible foreign-national customers receive five minutes of domestic calls.
• Additional domestic calls and SMS can be used through balance recharge.
• Korean-national customers can use the service as a data-only eSIM.

3. LG U+ Prepaid eSIM Conversion

This is an eSIM conversion option for eligible LG U+ prepaid phone plans.

• Compatible iPhones only
• Android devices are not supported
• Device information must be submitted before activation
• Identity verification is required

Always check the individual product page before purchasing because available services vary by product.

eSIM compatibility depends on the device model, country of purchase, regional version, and carrier configuration.

iPhone

Most iPhones from the iPhone XS, iPhone XS Max, and iPhone XR generation onward support eSIM.

To check your device:

Settings → General → About

Confirm that an EID is displayed.

You should also confirm that the Add eSIM option is available under your cellular settings.

Android

eSIM support varies depending on the manufacturer, model, country of purchase, and carrier.

Many recent Samsung Galaxy Z Flip, Galaxy Z Fold, Galaxy S-series, Google Pixel, and other Android devices may support eSIM.

Check:

Settings → Connections → SIM Manager

Confirm that:

• An EID is displayed
• The Add eSIM menu is available

You may also dial:

*#06#

and check whether an EID appears.

Even devices with the same model name may have different eSIM capabilities depending on the country or carrier.

Yes.

A carrier-locked device may prevent the installation or use of an eSIM from another provider.

Please contact your original mobile carrier before purchasing if you are unsure whether your phone is unlocked.

No.

Korea USIM's LG U+ prepaid eSIM conversion is available only for compatible iPhones.

Android users should select a compatible physical SIM, an SKT product, or a travel data eSIM according to their device and service needs.

This applies only to customers who selected the LG U+ eSIM conversion option.

On your iPhone, open:

Settings → General → About

Send screenshot(s) clearly showing:

• Device Name
• Storage Capacity
• EID
• IMEI1
• IMEI2

If all information does not fit on one screen, multiple screenshots may be submitted.

The eSIM QR code or PDF will be sent to the email address entered during checkout.

Orders are normally delivered during business hours on the same day, but immediate delivery is not guaranteed.

Please check:

• The email address entered during checkout
• Inbox
• Spam or junk folder
• Promotions folder

Yes. Installing the eSIM before departure is generally recommended.

Before departure:

• Connect to stable Wi-Fi
• Add the eSIM through your phone's settings
• Do not use the travel eSIM for mobile data before arriving at your destination unless the product instructions specifically allow it

For most Travel Data eSIMs, simply installing the eSIM does not start the service period.

The service period normally begins when the eSIM first connects to a supported mobile network at the destination.

Unless otherwise stated on the product page, validity is generally calculated in 24-hour units from activation.

For example:

• 1-day plan: Approximately 24 hours
• 3-day plan: Approximately 72 hours
• 5-day plan: Approximately 120 hours

After arriving at your destination:

• Turn on the eSIM line
• Select the eSIM for mobile data
• Turn on data roaming for the eSIM
• Restart the phone if necessary

The exact activation and validity method may vary by product, so always check the product page and the instructions sent with your eSIM.

1. Connect to stable Wi-Fi.
2. Open Settings.
3. Select Cellular or Mobile Service.
4. Select Add eSIM.
5. Select Use QR Code.
6. Scan the QR code.
7. Complete the installation.
8. After arrival, turn on the eSIM and data roaming.

Do not scan the QR code only through the regular camera application. It must be added through the phone's Add eSIM menu.

1. Connect to stable Wi-Fi.
2. Open Settings.
3. Select Connections.
4. Select SIM Manager.
5. Select Add eSIM.
6. Scan the QR code.
7. Complete the installation.
8. After arrival, turn on the eSIM, select it for mobile data, and enable data roaming.

Menu names may differ depending on the manufacturer and device model.

No. Most eSIM QR codes are valid for one installation only.

After installation:

• Do not delete the eSIM
• Do not install it on another device
• Do not reset the eSIM profile
• Do not repeatedly scan the QR code
• Do not reset your phone before or during the trip

A used, deleted, or transferred eSIM may not be reissued.

Please install the eSIM only on the device you intend to use.

Yes, if your phone supports Dual SIM.

You may keep your original SIM active for calls and messages while using the eSIM for mobile data.

To avoid unexpected roaming charges:

• Select the eSIM as the mobile data line
• Turn off data roaming for your original SIM
• Disable automatic mobile data switching if necessary

The message “Activating” may appear when the eSIM has been installed before arriving at the destination.

This is often normal because the eSIM cannot connect to its supported network until arrival.

After arriving:

• Turn on the eSIM line
• Select the eSIM for mobile data
• Turn on data roaming
• Restart the phone

This is normal for a data-only eSIM.

Travel data eSIMs generally do not include a mobile number, standard calls, or SMS.

A phone number may be displayed only on products that specifically include a Korean mobile number.

Available services depend on the selected plan and customer eligibility.

1-Day Official SKT eSIM

The 1-day plan is a data-only service.

It does not include:

• Korean phone number service
• Voice calls
• SMS

Foreign-National Customers

Eligible foreign-national customers using a qualifying plan can use a Korean mobile number after completing the required foreign passport verification.

After verification, available services include:

• Unlimited mobile data
• Korean mobile number
• Five minutes of free domestic calls
• Additional domestic calls and SMS through balance recharge

Calling functions may remain unavailable until the required passport verification has been completed.

Korean-National Customers

Korean-national customers can use the official SKT eSIM as a data-only service.

• Mobile data: Available
• Voice calls: Not available
• SMS: Not available

No passport or other identification is required for Korean-national customers using the official SKT eSIM as a data-only service.

Even if a Korean phone number appears in the device settings, Korean-national customers cannot use voice calls or SMS.

Recharge conditions depend on the product.

Travel Data eSIM

Most travel data eSIMs are single-use products and cannot be recharged.

When the service period ends, a new eSIM must normally be purchased.

Official SKT Roaming Center eSIM

Eligible foreign-national customers may recharge the balance for additional domestic calls and SMS after passport verification.

Please note:

• Recharge balance cannot be cancelled or refunded after processing.
• Unused balance is also non-refundable.
• Recharge only the amount you expect to use.
• We recommend starting with a small amount and adding more only when necessary.

The data validity period and the call/SMS balance are separate.

LG U+ Prepaid eSIM

Recharge and extension conditions follow the relevant LG U+ prepaid phone plan.

Please purchase the correct LG U+ recharge product before the current plan expires.

Most Korea USIM data eSIM products support hotspot and tethering.

However, availability may depend on:

• Destination
• Product
• Device
• Local network policy

Please check the individual product page for exact conditions.

Eligible foreign-national customers purchasing the official SKT product may select a physical SKT SIM instead.

The physical SIM can be collected at an SKT Roaming Center at:

• Incheon International Airport Terminal 1
• Incheon International Airport Terminal 2
• Gimpo International Airport
• Gimhae International Airport
• Daegu International Airport

A pickup voucher will be sent separately to the registered email address after the reservation is completed.

Please bring:

• Your original foreign passport
• Your SIM pickup voucher

Korean-national customers cannot collect the physical SIM under this product and must use the data-only eSIM option.

It depends on the eSIM product.

Travel Data eSIM

Passport or identity verification is generally not required.

However, selected products for certain destinations may require traveler registration or passport verification before use, including:

• Taiwan
• China
• Hong Kong
• Macau

If traveler registration is required, please follow the instructions sent with your order.

Service may not begin until the required registration has been completed.

Official SKT Roaming Center eSIM

Foreign-national customers must complete foreign passport verification to use eligible Korean phone number and calling services.

The 1-day Official SKT eSIM is data-only.

Korean-national customers using the Official SKT eSIM as a data-only service do not need to submit a passport or other identification.

LG U+ Prepaid eSIM Conversion

Identity verification is required because the eSIM is connected to a Korean prepaid phone service.

Selected China eSIM products include international internet routing.

A separate VPN application or paid VPN service is generally not required.

After the eSIM is properly connected, services such as Google, YouTube, Instagram, LINE, and KakaoTalk can normally be accessed through the eSIM connection.

Please check the following:

1. The eSIM line is turned on.
2. The eSIM is selected for mobile data.
3. Data roaming is turned on for the eSIM.
4. Your original SIM is not selected for mobile data.
5. Data roaming is turned off for your original SIM.
6. Airplane mode is turned off.
7. The phone has been restarted.
8. The device is within a supported coverage area.

If it still does not connect, contact Korea USIM and send screenshots of:

• SIM Manager or Cellular settings
• Mobile data settings
• Data roaming settings
• Any error message

Please confirm that:

• The phone supports eSIM
• An EID is displayed
• The device is carrier-unlocked
• The QR code has not already been used
• You are connected to stable Wi-Fi
• You selected Add eSIM in the phone settings
• You are not scanning only with the ordinary camera application

Displaying the QR code on another phone, tablet, or computer usually makes scanning easier.

If the QR code has already been installed or used, do not delete the existing eSIM and attempt to reinstall it.

Refunds may be restricted after the eSIM QR code has been:

• Issued
• Delivered
• Installed
• Activated
• Used

An eSIM QR code is a digital product and may not be reusable after delivery or installation.

Refund eligibility is determined according to the product status and the Korea USIM refund policy.

Please check your device compatibility, destination, and travel dates carefully before ordering.

Customer support is available in:

• Korean
• English
• Japanese

Email: allnet3382@naver.com
KakaoTalk ID: allnet3382

When contacting us about an eSIM issue, please include:

• Order number
• Customer name
• Destination
• Device model
• Arrival date
• Selected product and duration
• Screenshot of the SIM settings
• Screenshot of any error message