There are no upfront fees for applying for a loan through Prosper. A one-time fee is charged if your loan is funded and money is transferred to you.
This fee is called the “Origination Fee” and is a percentage of the amount borrowed (2.4%-5%, depending on Prosper Rating). It is taken from the loan immediately, before loan proceeds are transferred to your account. This means that if you apply for a loan and need an amount to purchase something specific or pay off a balance on a credit card, make sure you ask for enough to cover both the expense and the fee.