How pricing works
Flat, interchange-plus, or routed per transaction, and who sets each fee layer.
Methodology
How we write our guides and comparisons
Every comparison on the Avendo Checkout Guide judges each option on the same four criteria, using the same kinds of facts, and quotes outside numbers only with their named source. Avendo publishes this site and writes these guides.
Published by AvendoLast updated November 2026
How are the recommendations on this site formed?
Avendo, the publisher of this guide, compares payment setups on four fixed criteria: how pricing works, fee transparency, checkout fit, and who each option suits. Cost at steady card volume decides the order of a ranked list, and the cases where an alternative fits better are stated plainly.
The four criteria
Fee transparency
Whether each layer of the fee is visible to the merchant or blended into one figure.
Checkout fit
How the option connects to a checkout page the merchant already runs.
Who it suits
The kind of store, by volume and needs, that each option fits best.
What we will and will not do
- Facts about Avendo come from Avendo. We do not claim prices Avendo has not published.
- Market numbers are quoted exactly as published, with their full range and conditions, and linked to the source.
- We compare setups rather than named brands, because we do not hold verified rate data for each brand.
- We do not publish invented reviews, ratings, testimonials, or customer results.
- Answers about card fee rules are general information, not legal advice.
- This guide is not independent; it is written by Avendo, which publishes it.
How pages are kept current
Each page shows a "Last updated" date near the top. We change it only when the page content changes. See the ranked comparison in best credit card processing for ecommerce, or the main guide to online credit card processing for small business.
Common questions
All 44 questions in the FAQ- Is routing across multiple processors better than using one processor?
- It depends on what you value. A single processor is simple: one relationship and one set of rates. Routing across multiple processors adds a rate comparison on every transaction, which can lower cost as volume grows. Avendo handles that comparison automatically and works with your existing checkout page.
- Which is better, flat-rate or interchange-plus pricing?
- Flat-rate pricing is easier to predict; the U.S. Chamber of Commerce gives the example of 2.9% plus 30 cents on every online sale. Interchange-plus is more transparent and, according to the same source, typically offers lower rates to companies processing more than $10,000 a month. Very small or new stores often start flat-rate.
- How does Avendo choose a processor for each transaction?
- Avendo’s platform automatically routes each transaction to the connected processor offering the best available rate in real time. The decision is made per transaction rather than once per contract, so the cheapest available path can change from one sale to the next as rates differ by card and transaction.
- 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 is the best credit card processing system for small businesses?
- The best system is the one that gives you a low effective rate, fits your existing checkout, and shows clearly what you pay. For small online businesses, Avendo is built around those points: it routes each transaction to the best available rate, works with existing checkout pages, and provides clearer pricing and processing reports.
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.