This is how you "split" a purchase on Amazon with VISA gift cards
Every once in a while I get a VISA gift card.  If you want to use it on AMAZON to pay for part of a purchase, you can't split it with any other credit card in your account.  But there is a workaround!  Purchase an AMAZON electronic gift card in the amount of your VISA gift card, pay for it entirely with the VISA gift card, then when you get the confirmation email, add the AMAZON e-gift card to your account.  Then you can "split" a purchase between your Amazon balance and any credit card.  I've done this many times.
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