These do NOT stack. US only. Check with your local GameStop to see if they have $10 Microsoft currency cards in-stock, as a couple customers reported them being in stock in their area. If so, you will be getting 800MSP worth for $5.00 each. No tax applied. Good on any item in stock in the store. Will not work on pre-orders. Again, these do NOT stack, so don't think you're gonna buy 50 and get an Xbox One at less than 1/4 price.