Payment Gateway vs Payment Processor vs Payment Aggregator: Who Does What

If you've read a payment provider's pricing page, a developer guide from abroad and an RBI notification in the same week, you've seen the same words used three different ways. "Payment processor" is the worst offender. In American writing it often means the whole service a business signs up for. In Indian regulation it isn't a category at all.

This guide sorts out the four roles that actually exist in an Indian online payment, using RBI's own definitions where there are any. If you only need the gateway-versus-aggregator distinction and what RBI's 2025 rules require of each, our guide to payment gateway vs payment aggregator covers that in depth. This one adds the processor and the acquiring bank, which is where most of the confusion comes from.

Before the detail, the short version:

Behind all four sit the networks (card networks for cards, NPCI for UPI) and the customer's own bank, called the issuer for cards and the remitter bank in UPI.

RBI defines a payment gateway as an entity that provides technology infrastructure to route and facilitate processing of a payment transaction without any involvement in handling of funds. That last part is the whole point. A gateway encrypts the payment details, sends them on, receives the answer and tells your system. It never holds your customer's money, even for a moment.

Because it doesn't handle funds, a pure gateway falls outside RBI's payment aggregator rules, though RBI encourages gateways to follow its baseline technology recommendations. Aggregators, in turn, are allowed to use a gateway's services under RBI's outsourcing rules. So a single brand can be a gateway in one arrangement and an aggregator in another.

"Processor" describes a job, not a licence. When a payment is authorised, cleared between banks and settled, someone has to run the systems that format, route and record those messages for the bank on the merchant's side. That's processing. It's done either by the acquiring bank itself or by a technology company working on the bank's behalf.

In India the regulated party in that chain is the acquiring bank (and the network). A company that runs processing systems for a bank typically does so as a technology service provider to that bank, under the bank's responsibility. Our explainer on technology service providers covers how that's overseen.

So when an Indian business is offered a "payment processor", it's worth asking what exactly is meant: a gateway, an aggregator, or a bank's acquiring service. The answer decides who holds your money and who you complain to.

RBI defines a payment aggregator as an entity that facilitates aggregation of payments made by customers to merchants through one or more payment channels, through the merchant's interface (physical or virtual), and subsequently settles the collected funds to those merchants. Unlike a gateway, it handles money.

The acquirer is the bank that accepts a payment on the merchant's side and settles it. For cards, it's the bank that has the relationship with the card networks and receives the money from the cardholder's bank through the network. In UPI, NPCI's rules use "acquirer" for the payee PSP: the bank through which a merchant is onboarded to receive UPI payments.

Most small and mid-size businesses never sign with an acquiring bank directly. Their aggregator does, and the aggregator's escrow account sits between the acquirer and the merchant. Large businesses sometimes contract with an acquiring bank directly, usually with a gateway on top, and receive settlements straight from the bank.

The differences that matter to a business:

A customer pays ₹10,000 by card on a website that uses a payment aggregator. Here's who does what:

With UPI the shape is the same but the names change: the customer's bank (remitter) debits, the merchant's payee PSP (acquirer) receives, and NPCI settles between the banks on a net basis several times a day through RBI's RTGS system. If the merchant uses an aggregator, the money then reaches the aggregator's escrow and is settled to the merchant on the agreed schedule. Our guide to how online card payments work follows the card version step by step, from authorisation through capture and settlement to refunds.

You don't need to memorise the plumbing. You do need clear answers to these, in writing, before you sign:

Some businesses connect to more than one gateway or aggregator, to accept more methods, to keep payments running when one provider has trouble, or to route each payment to the provider most likely to approve it. A payment orchestration layer sits above those providers and decides where each payment goes. It's another technology layer: the providers it connects to still collect, hold and settle the money under their own agreements with you. Our explainer on smart payment routing shows how that decision is made.