Virgin Mobile USA phones work strictly within the USA.
Virgin Mobile USA phones use the Sprint Nationwide Network which extends ONLY throughout the 48 U.S contiguous states, Hawaii, Washington DC, Puerto Rico, and US Virgin Islands. The Virgin Mobile USA phones do not roam across other phone networks either. For these reasons the Virgin Mobile USA phones work strictly within the USA and when located outside the USA, will not send/receive calls or messages nor provide web access. There are no options available to use Virgin Mobile USA phones outside the USA.
Sorry, all phones, devices, and SIM cards from Virgin Mobile are locked. They can't be used with any other carrier.
Virgin Mobile's Apple iPhones contain a special SIM card that is paired with one iPhone. This special SIM card can't be used with another phone.
Virgin Mobile answered your question in the FAQs:
• About Removable UICC Cards
All 4G LTE (non WiMax) phones require a Universal Integrated Circuit Card (UICC).
• What is a UICC card?
A UICC card is the physical smart card that is pre-inserted on your device and allows for LTE network authentication/ access. It's a new generation SIM (Subscriber Identification Module) card. No customer-specific information-like contacts, address book, or account information, photos, or personal data- is stored on this card.
READ MORE AT: http://virginmobileusa.custhelp.com/app/answers/detail/a_id/5793
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