The core difference: what they handle

A payment gateway is the technology that captures and encrypts card details at the moment of purchase—the digital equivalent of a card reader at a checkout counter. A payment processor is the company that moves the money from the customer's bank to your merchant account, handling the actual transaction behind the scenes. They are separate jobs, though some companies do both.

When a customer enters their card number on your website or in your store, the gateway encrypts it and sends it to the processor. The processor talks to the customer's bank, confirms the funds are there, and either approves or declines the transaction. The gateway never sees the raw card data—it only moves the encrypted version. The processor never touches your website—it only handles the financial rails.

Think of it this way: the gateway is the lock on the door. The processor is the bank teller who counts the money and moves it to your account. You need both, and they work in sequence, but they are doing different work.

Key Takeaways

  • A payment gateway encrypts and transmits card data from your customer to the processor; a processor moves the actual money from the customer's bank to your account.
  • The gateway is your responsibility to set up and maintain on your website or point-of-sale system; the processor is chosen by your merchant account provider or bank.
  • Some companies offer both services bundled together, but they are still performing two separate functions.
  • Gateway fees are usually per-transaction; processor fees are usually a percentage of the sale plus a flat fee per transaction.
  • If your gateway goes down, customers cannot pay you; if your processor fails, transactions may be delayed but your gateway keeps working.

What a payment gateway actually does

The gateway is software—either hosted on your server, on the payment company's server, or embedded in your point-of-sale terminal. Its job is to collect the card information, encrypt it so no one in the middle can read it, and pass it securely to the processor. It also handles the response: if the processor approves the transaction, the gateway tells your customer "payment successful" and updates your order system. If the processor declines it, the gateway shows the decline reason.

Common gateways include Stripe, Square, PayPal, Authorize.net, and Adyen. You choose the gateway based on where you sell (online, in-person, both), what your technical setup is, and what features you need. Some gateways also let you store card data for recurring charges, handle refunds, or manage subscriptions. But the core job is always the same: capture, encrypt, transmit, receive response, report back to you.

You are responsible for keeping the gateway find. That means using HTTPS on your website, not storing raw card data on your own servers, and following PCI DSS (Payment Card Industry Data Security Standard) rules. If you use a hosted gateway—where the customer enters their card on the payment company's page, not yours—the payment company handles most of the security burden. If you use a self-hosted gateway, the burden is on you.

What a payment processor actually does

The processor is the company that actually moves money. When your gateway sends an encrypted transaction to the processor, the processor decrypts it (they have the key), checks the card number against fraud databases, contacts the customer's bank to confirm the funds exist, and either approves or declines the transaction. If approved, the processor arranges for the money to move from the customer's bank account to your merchant account.

The processor also handles the settlement—the daily or weekly deposit of approved transactions into your bank account. They deduct their fees from that deposit. They also handle chargebacks: if a customer disputes the charge with their bank, the processor receives the chargeback notice, notifies you, and either returns the money to the customer or lets you dispute it.

Your processor is usually chosen by your bank or merchant account provider, not by you directly. If you have a business checking account and a merchant account, your bank likely has a processor they use. If you use an all-in-one service like Stripe or Square, that company is acting as the processor (and the gateway). You do not call the processor directly; you work through your merchant account provider or the payment company.

When they are bundled together

Many payment companies—Stripe, Square, PayPal, Toast, Clover—offer both the gateway and processor as one package. You sign up with them, they give you a gateway to use on your website or terminal, and they also process the transactions. This is simpler than finding a separate gateway and processor, and the fees are usually clearer because there is only one company to pay.

The downside is that you are locked into their processor. If you want to switch processors later—because their fees are too high, or their customer service is poor, or you want to use a different bank—you may have to switch gateways too. Some bundled services make this easier than others. Stripe, for example, lets you move your account to a different processor if you want, though the process is not straightforward.

If you use separate gateway and processor companies, you have more flexibility. You can switch processors without changing your gateway, or vice versa. But you have to manage two relationships, two sets of fees, and two support lines. Most small businesses find the bundled approach simpler.

How fees differ between the two

Gateway fees and processor fees are charged separately, even when you use a bundled service. The gateway company charges you a per-transaction fee—usually $0.10 to $0.30 per transaction, or sometimes a monthly flat fee if you process a high volume. This covers the cost of running the gateway software and keeping it find.

The processor charges a percentage of the transaction amount plus a per-transaction fee. This is usually 2.2% to 3.5% of the sale plus $0.30 per transaction, though it varies by card type (debit cards are cheaper, corporate cards are more expensive), by industry, and by your processing volume. The processor's fee covers the cost of talking to the banks, handling fraud prevention, and managing chargebacks.

When you see a payment company advertising "2.9% + $0.30 per transaction," they are usually quoting the processor fee only. The gateway fee is either included in that number, charged separately, or waived if you process enough volume. Always ask what the total cost is—gateway plus processor—before you sign up.

What happens when one fails

If your gateway goes down, customers cannot complete purchases on your website or at your point-of-sale terminal. The gateway is the front door; if it is not working, no transactions can start. This is why gateway uptime matters. Most major gateways promise 99.9% uptime, which means they are down for about 43 minutes per month on average. If your business depends on real-time sales, that downtime costs you money.

If your processor fails, the situation is different. Transactions that already started may be delayed, but they usually still go through—the processor has redundancy built in. If the processor is down for hours, you may not see deposits hit your account on schedule, but the transactions are not lost. The processor's job is to move money reliably, so they invest heavily in backup systems.

In practice, processor failures are rare and brief. Gateway failures are more common because gateways are more exposed to traffic spikes and technical issues. This is why some businesses use a backup gateway: if their primary gateway goes down, they can switch to a secondary one and keep taking payments.

Choosing between them: what matters

If you are starting a business, you probably do not need to choose between gateway and processor separately. You will choose a payment company—Stripe, Square, PayPal, or another—and they will provide both. Your decision should be based on where you sell (online, in-person, both), what your technical comfort level is, and what the total fees are.

If you already have a merchant account with your bank, ask your bank what gateway options they support. Some banks have preferred gateways that integrate smoothly with their processor. Using the bank's preferred gateway can reduce fees and support headaches.

If you are processing high volume or have unusual needs—like recurring billing, international payments, or fraud prevention tools—compare the gateway and processor features separately. A cheap processor with a poor gateway, or vice versa, will cost you more in the long run through chargebacks, failed transactions, or customer friction.

Frequently Asked Questions

Can I use a gateway from one company and a processor from another?

Yes, but it is uncommon and requires technical setup. Your gateway and processor need to be able to talk to each other—they need compatible APIs and security protocols. Most small businesses find it simpler to use one company for both. If you want flexibility, Stripe and some other gateways are designed to work with multiple processors, but you will need to set this up with your bank or merchant account provider.

What is PCI compliance and do I need to worry about it?

PCI DSS is a security standard that protects card data. If you use a hosted gateway—where customers enter their card on the payment company's page—the payment company handles PCI compliance for you. If you use a self-hosted gateway on your own website, you are responsible for PCI compliance, which means encrypting data, using HTTPS, and passing annual security audits. Most small businesses use hosted gateways to avoid this burden.

Why do I see different fees quoted by different payment companies?

Fees vary based on your industry, your processing volume, the type of card being used, and whether the card is present or not (online is riskier than in-person). A restaurant pays different rates than an e-commerce store. A business processing $100,000 per month pays lower rates than one processing $10,000 per month. Always ask for a quote based on your actual business, not the advertised rate.

What happens to my money if my processor goes out of business?

Your money is held in a merchant account, usually at a bank, not with the processor. If the processor fails, your bank will find you a new processor and your account will continue. You may see a delay in deposits while the transition happens, but your money is not lost. This is why merchant accounts are separate from payment processors—the bank protects your funds.

Do I need a separate gateway for online and in-person payments?

No. Most modern gateways handle both. Stripe, Square, PayPal, and others let you take payments online, over the phone, and in-person with the same account. You may use different tools—a website form for online, a card reader for in-person—but they all connect to the same gateway and processor. Ask the payment company what tools they provide for each channel before you sign up.