Vanilla gift cards are a specific type of prepaid Visa card. In order to use these or other prepaid cards, please check the user agreement or card issuer website for information on where you can use them.

Some prepaid cards require you to register an account with them before being able to use it online, and some cards do not work online at all. We don't have any information about specific payment types.
Additionally, some payment services like Facebook, Xsolla, Paypal, etc may not accept these types of cards. Check the individual payment processor for more information. 

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Vanilla FAQ
Paypal Gift Card Help
Facebook Payment Methods
Xsolla Gift Card Help