Gateway vs Processor vs Switch vs Acquirer: What Is the Difference?

Gateway, processor, switch and acquirer are four terms that get used loosely — and sometimes interchangeably — in the payments industry, which makes them confusing when you are comparing providers. Each one describes a distinct role in moving a card payment from your customer to your bank account.

In practice a single company often performs more than one of these roles, which is where the confusion comes from. This page separates them out so you know what you are actually buying.

The four roles at a glance

What is a payment gateway?

The gateway is the front door of a transaction. It is the technology that securely captures the customer's card details on your website, app or payment link, encrypts them, and sends them onwards for authorisation. The gateway also returns the result — approved or declined — to your checkout.

Because the gateway handles raw card data, it carries most of the PCI DSS security burden. Using a provider's gateway, rather than touching card data yourself, is what keeps your own compliance scope small. How much of that scope you take on depends on your integration choice; see hosted, embedded and API checkout.

What is a payment processor?

The processor does the heavy lifting behind the gateway. It takes the transaction from the gateway, communicates with the card networks and the relevant banks, manages authorisation requests and responses, and handles clearing and settlement files afterwards. Processors also deal with operational events such as refunds and reversals.

Merchants rarely contract with a processor directly. Your payments provider either is the processor or has a processing relationship, and the distinction mostly matters when diagnosing where in the chain a payment failed. For what happens when a payment is declined, see card declines and response codes.

What is a switch?

A switch is routing infrastructure. It receives a transaction and directs it to the correct destination — the right card network, the right issuing bank, or the national payment system. In South Africa, interbank transactions are cleared through national payments infrastructure, and switches are the plumbing that connects the participants.

You will never integrate with a switch as a merchant. The term appears in industry conversation because some companies market themselves as switches, meaning they specialise in that routing layer rather than in merchant-facing services.

What is an acquirer?

The acquirer, or acquiring bank, is a licensed bank that is a member of the card schemes (such as Visa and Mastercard) and is authorised to accept card payments on behalf of merchants. The acquirer:

• Sponsors your merchant account and merchant ID
• Receives settled funds from the card networks and pays them to you
• Carries the financial liability for your chargebacks and refunds
• Enforces scheme rules and risk requirements on your account

In South Africa the major acquiring banks include divisions of the big retail banks. Most small and medium businesses do not contract with an acquirer directly; instead, a payments provider aggregates merchants under its own acquiring relationships.

How do the roles fit together in one transaction?

For a typical online card payment:

1. The customer enters card details at checkout — the gateway captures and encrypts them.
2. The processor sends an authorisation request via the card network, with the switch routing it to the customer's issuing bank.
3. The issuing bank approves or declines, often after 3-D Secure verification, and the response travels back the same way.
4. Later, cleared funds flow from the issuing bank through the network to the acquirer, which settles them to your bank account.

Why does this matter when choosing a provider?

Full-service providers such as Kwik bundle the gateway, processing and acquiring relationships into one agreement, so you get one contract, one settlement and one support channel. When comparing providers, ask which roles they perform themselves and which they outsource — it affects support, reliability and how quickly issues get resolved. For the broader transaction flow, see how payments work, or return to the accepting payments hub.