How does an acquirer work?
The acquirer holds the merchant account, either directly or through a PSP acting as a payment facilitator. It assigns the merchant category code, receives authorization requests, routes them through Visa, Mastercard or a domestic scheme to the issuing bank and returns the answer. Later it clears the approved transactions with the scheme, receives the funds and settles them to the merchant or PSP after fees.
Why does the acquirer matter for approval rate?
Issuers judge each request partly by who sends it. A card issued in Brazil may be approved more often when processed by a Brazilian acquirer than by a European one, because the issuer sees a domestic transaction, a known counterparty and no cross-border risk flag. As an illustrative example: if a market’s cards approve at 85% domestically and 60% cross-border, moving 10,000 monthly payments to a local acquirer adds about 2,500 approvals. Cost moves the same way, since cross-border transactions carry extra scheme fees.
How is an acquirer different from a PSP and an issuer?
The issuer is the cardholder’s bank and decides whether to approve. The acquirer is the merchant’s side of the card network and carries scheme liability for the merchant. The PSP is the commercial layer the merchant usually deals with, which may be an acquirer itself or work with several. Acquirers are also the parties scheme monitoring programs such as Visa VAMP measure, so a merchant’s chargeback ratio is the acquirer’s problem too.
Where does Omno use it?
Omno does not acquire. It connects to PSPs, which work with acquirers. Routing rules let a merchant send traffic to the PSP route that acquires domestically for a given card country, and the routing-decision log shows which route processed each payment.