Earlier this month, Amazon changed the pricing structure for micropayment (aggregate) transactions performed with the Flexible Payments Service (FPS). FPS no longer charges a per-transaction fee for payments made from a prepaid or postpaid instrument. Fees are only changed when money is transferred into an instrument: to fund a prepaid instrument, or to settle a postpaid instrument.
The new fee structure makes the FPS micropayment instruments much more attractive. Using the prepaid and postpaid instruments, you can aggregate many small payments into a few large transactions to minimise the cost of transaction fees over these payments. Previously, Amazon took a cut of each individual payment as well as imposing transaction fees to fund and settle the instruments, but that extra fee burden has been removed.