A remittance fee is the stated charge that a bank, money transfer operator or app applies to an international transfer. It is paid by the sender on top of the amount being sent, and it may be a flat sum, a percentage of the principal, or a scale that steps up with the amount. The fee usually depends on the destination, how the transfer is funded and how it is paid out, with cash services costing more than account-to-account ones.
The fee is only one part of what the sender pays. Providers also earn an FX markup by converting at a rate less favorable than the market rate, and a transfer advertised with no fee can still be expensive once that margin is counted. The combined figure is the remittance cost. The fee is typically shared between the operator and its sending and paying agents.