Payment gateway
The technical layer that carries a payment request from a website, app or terminal to the acquirer. It moves data; it does not hold a merchant account and it does not settle money. The word is used loosely — many companies sold as "payment gateways" are actually acquirers, resellers or both — which is why the question to ask is who holds the licence and who pays you, not what the product is called.
Why it matters to a merchant
The word is the most over-used one on a Singapore payments proposal, because it is the one merchants search for and vendors therefore adopt regardless of what they actually are. Read it as a description of a function, not of a company: a gateway moves the transaction, and something else holds the licence and the money. When a proposal says "gateway" and nothing else, the missing information is who the acquirer is.
Read more: Acquirer, gateway, PSP: what the words actually mean
Where this comes up
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Related terms
In this section: Who does what