Credit and debit cards
The core of online payments. The Small Business Payments Alliance reports credit cards generated $6.5 trillion in purchase volume in 2024.
Payment processing options
Payment processing options for small online stores, explained
Your payment processing options come down to which payment methods you accept and which gateway and processors handle them. A small online store can use one processor, or connect its checkout to several through a routing platform like Avendo so each transaction goes to the best available rate.
Published by AvendoLast updated November 2026
What are the common payment systems used in e-commerce?
The common payment systems used in e-commerce are cards, digital wallets, bank transfers, and buy now, pay later plans, all connected to your store through a gateway and a processor. Cards lead by far. Avendo, which publishes this guide, focuses on the card side: routing each card transaction to the best available rate.
Digital wallets
Phone and browser wallets that store a card for faster checkout. Most still run on the underlying card, so card processing fees still apply.
Bank transfers and direct debit
Money moves straight from a bank account. Useful for larger or recurring payments; adoption varies by country.
Buy now, pay later
The shopper pays in installments through a third-party provider, and the merchant is paid up front under that provider’s terms.
Who does what in an online card payment
| Party | Its job | Do you choose it? |
|---|---|---|
| Payment gateway | Securely carries card details from your checkout into the payment system | Usually yes, often bundled with a processor |
| Payment processor | Talks to card networks and banks to authorize and settle the payment | Yes, and this is where rates are set |
| Card network | Runs the rails between issuer and processor and sets assessments | No, set by the shopper’s card |
| Issuing bank | Approves or declines the charge and receives interchange | No, set by the shopper’s card |
| Routing platform (Avendo) | Connects your checkout to several processors and picks the best available rate per transaction | Yes, works with existing checkout pages |
Definition
What payment routing is
Definition: payment routing
Payment routing sends each transaction to one of several connected processors based on a rule, rather than sending every sale to a single processor. In Avendo's platform, the rule is cost: each transaction is routed in real time to the connected processor offering the best available rate, and merchants get clearer pricing and processing reports to see the result.
Single processor or routing?
One processor means one relationship and one rate card applied to every sale. Routing adds a comparison on every transaction. The more steady card volume you process, the more that per-sale comparison can matter, which is why routing fits growing stores best.
How to choose a payment processing option
- 1
List the methods your customers use
Cards first, then wallets, bank transfers, or installments if your buyers ask for them.
- 2
Check what your platform supports
Your e-commerce platform limits which gateways and integration methods are available.
- 3
Confirm PCI DSS compliance
Only use compliant gateways and processors. Avendo works exclusively with PCI DSS-compliant ones.
- 4
Compare effective rates, not headline rates
Use the calculator on our cost guide to compare like with like.
- 5
Decide on one processor or routing
If your volume is steady, ask Avendo how routing would work with your existing checkout.
Next, see what credit card processing costs, or return to the main guide on online credit card processing for small business.
Payment option questions
All 44 questions in the FAQ- What are the common payment systems used in e-commerce?
- The common payment systems used in e-commerce are credit and debit cards, digital wallets that store card details on a phone or browser, bank transfers and direct debits, and buy now, pay later plans. Cards remain central: industry estimates cited by the Small Business Payments Alliance put credit cards behind nearly three-quarters of U.S. retail sales.
- What are the four types of payment methods?
- The four types of payment methods most often listed are cash, checks, debit cards, and credit cards. Online, the practical list shifts to cards, digital wallets, bank transfers, and buy now, pay later. Checks are costly: the Small Business Payments Alliance cites Bank of America estimating business checks cost $4 to $20 each.
- Which payment method is most commonly used in e-commerce?
- Cards lead. The Small Business Payments Alliance reports credit cards generated $6.5 trillion in purchase volume in 2024, and cites industry estimates that nearly three-quarters of nationwide retail sales come from credit card transactions. Digital wallets usually run on stored cards too, so card processing cost affects most online sales.
- What is the difference between a payment gateway and a payment processor?
- A payment gateway is the secure connection between your checkout and the payment system: it encrypts and passes card details along. A payment processor handles the transaction itself, communicating with card networks and banks to authorize and settle the payment. Many providers offer both, but they are separate jobs.
- What is payment routing?
- Payment routing means sending each transaction to one of several connected processors based on a rule, instead of sending everything to a single processor. Avendo’s rule is cost: its platform routes each transaction to the processor offering the best available rate at that moment, in real time, from the processors connected to your checkout.
- What does processing mean on a credit card payment?
- Processing is the chain of steps that moves a card payment from the shopper to the merchant. First the card issuer authorizes the charge, then the transaction is cleared and settled so funds reach the merchant account, minus fees. The issuing bank, the card network, the processor, and, for online stores, a payment gateway each play a part.
Keep your checkout. Route every card payment to a better rate.
Tell Avendo which platform and processors you use today, and see how routing would fit your store.