A merchant acquirer is a licensed institution. It processes card payments for
merchants under one or more scheme licences. It holds the link to Visa, Mastercard
and the other networks. It takes the payment, captures the funds, and pays them to
the merchant — or to an aggregator, which then pays its sub-merchants.
For a merchant in one market and one vertical, a single acquirer usually works. For
everyone else, one acquirer is where the trouble starts. You get one underwriting
appetite, one rate card, one chargeback ratio, one uptime story. topropay sits in
front of several. So the question stops being "which acquirer" and becomes "what's
the right routing policy".
The rest of the page fills in the picture. How the platform routes across many
acquirers. What acquirer BIN and acquirer ID mean in the data model. And how the
connected acquirers line up with Visa, Mastercard and the other networks.