Guam & Saipan eSIM (Unlimited Data)

• Purchase a product
• Scan the QR code in the voucher sent to your email
• Register eSIM according to the registration method for your device operating system
• Expiration date: 180 days from purchase date

Operating hours:
Messenger Customer Center
24 hours a day, 365 days a year

Wired Customer Center
09:00 ~ 18:00 (Lunch time 12:00 ~ 13:00)
Closed on weekends and public holidays

contact :
Domestic: 1661-0158
Overseas (for local disabled only): (+)82-070-5097-6417
KakaoTalk Plus Friend: @Yusimsa

• Please make sure that your current mobile phone model supports eSIM before purchasing.
• After purchase, a voucher containing a QR code will be sent to the email address provided in your purchase information.
• If you cannot find your voucher after confirming your reservation, we recommend checking your spam mailbox first.
• There may be a problem where emails are not received due to a temporary error. If such an error occurs, please contact the Yusimsa Customer Center.
• This product allows unlimited data use at low speeds after using up all daily data allowance.
• This product calculates 24 hours as 1 day, and the validity period calculation and data use begin from the time of activation after registration.
• The number of days is deducted every 24 hours from the activation time, and the data is reset.
• This product cannot be used for calls or text messages other than data networks, hotspots, and tethering.
• The telecommunications company providing the network may change without prior notice, and cancellation and refund are not possible due to this.
• For the first time registration of eSIM, the device must be connected to the network, so please pre-register in Korea before departure or register using the free Wi-Fi upon arrival.
• If you have difficulty using eSIM or the connection is not working , do not remove the eSIM and be sure to contact the SIM card customer service center.
• eSIM products can only be registered and used on the terminal on which they were first registered, and cannot be re-registered on another terminal after registration.
• Registration method by device operating system
  • Before Departure (Korea), Learn More About How to Register Android
  • Before Departure (Korea), Learn More About How to Register iOS
  • After arriving in the country, learn more about how to register Android
  • After arriving in the country, learn more about how to register iOS

Refunds are only possible within 7 days of the purchase date.
However, refunds for the following month may be difficult to process, and refunds are not possible for products that have been used or have already been registered to the terminal.
Refund requests due to reasons such as activation failure, unavailability, or eSIM failure due to the nature of products used overseas may not be due to product issues but rather to the terminal being used, insufficient settings, or temporary communication failures. Therefore, only cases approved after consultation via the customer center (phone, email, KakaoTalk) using local Wi-Fi, etc. will be processed.
Refunds requested after returning to Korea without prior confirmation may not be processed.

Cancellation/refunds are only applicable to cases received during business hours (09:00-18:00) on weekdays.