What payment processing companies do

A payment processing company is the middleman that moves money from your customer's bank account or card to your business account. When someone pays you by card, that payment does not go directly to you — it passes through a processor, a payment gateway, and often a bank or two before it lands in your account. The processor's job is to verify the card is real, check that the customer has enough money, and send the transaction to the right bank.

Payment processors come in different shapes. Some are full-service processors that handle everything from taking the payment to depositing it into your account. Others are payment gateways that only handle the technology part — they encrypt the card data and send it somewhere else to be processed. Some are payment aggregators that let you start accepting payments without a merchant account, though usually at higher fees. Which one you need depends on your business size, the volume of transactions you handle, and whether you want to manage the relationship with a bank yourself.

Key Takeaways

  • Payment processors charge multiple fees — interchange fees (set by card networks), assessment fees, and their own processing markup — that add up to 2 to 4 percent of each transaction for most small businesses.
  • Interchange fees are set by Visa, Mastercard, and American Express and are the same everywhere; what differs is the processor's markup on top of that.
  • Monthly fees, statement fees, PCI compliance fees, and chargeback fees are separate from per-transaction costs and vary widely by processor.
  • Processors that do not require a merchant account (payment aggregators) are faster to set up but charge higher per-transaction fees than processors that do.
  • The processor you choose affects how fast you get paid, what payment methods you can accept, and how much you pay when something goes wrong.

How fees break down: interchange, assessment, and markup

Every card transaction involves three layers of fees, and understanding them matters because they hit your bottom line differently. Interchange fees are set by Visa, Mastercard, American Express, and Discover — not by your processor. These fees go to the customer's bank (the issuer) as compensation for the risk of the transaction. Interchange rates vary by card type (a rewards card costs more than a basic card), by industry (restaurants pay different rates than retail), and by how the card is processed (swiped, keyed in, or online). You cannot negotiate interchange fees because they are the same everywhere.

On top of interchange, the card networks charge assessment fees — a small percentage that goes to Visa, Mastercard, or American Express for running the network. These are also fixed and the same across all processors.

What your processor charges on top of interchange and assessment is their markup, and this is where you can shop around. Some processors charge a flat percentage (say, 2.9 percent plus 30 cents per transaction). Others use interchange-plus pricing, where they charge you the actual interchange rate plus a fixed markup — this is usually cheaper if you process a high volume. Still others use tiered pricing, where they bucket transactions into may have access to, mid-may have access to, and non-may have access to categories and charge different rates for each, which can hide higher costs in the fine print.

Monthly and hidden fees beyond per-transaction costs

Per-transaction fees are only part of what you pay. Most processors charge a monthly statement fee (usually $5 to $15) just to send you a statement. Many charge a monthly minimum fee — if your transaction fees do not add up to that minimum, you pay the difference. Some charge PCI compliance fees ($50 to $300 per year) for handling the security standards that protect card data, though some processors include this in their base fee.

If a customer disputes a charge or a card is declined, you may pay chargeback fees ($15 to $100 per dispute) and decline fees (50 cents to $1 per failed transaction). Some processors charge for batch fees (closing out your daily transactions), gateway fees (if you use a separate payment gateway), or early termination fees if you leave before your contract ends. Read the fee schedule carefully — processors often bury these in the terms, and they add up fast on a small margin business.

Merchant accounts versus payment aggregators

A merchant account is a bank account specifically for card payments. To get one, you explore to a bank or processor, they underwrite your business (checking your credit, your industry, your processing history), and if approved, you sign a contract. Once you have a merchant account, you can accept cards at lower per-transaction rates because the bank has vetted you and taken on less risk. The downside is the process takes days or weeks, and you may be turned down if your credit is poor or your industry is considered high-risk (like adult services or gambling).

Payment aggregators (like Square, Stripe, or PayPal) do not require a merchant account. You sign up online, often in minutes, and start accepting payments when ready. The trade-off is higher per-transaction fees — usually 2.9 percent plus 30 cents or higher, compared to 1.5 to 2.5 percent for a merchant account. Aggregators are designed for small businesses, freelancers, and one-off sellers who do not process enough volume to justify the underwriting process. If you grow and process thousands of dollars a month, switching to a merchant account with a lower-cost processor usually saves you money.

How settlement and payout timing work

When a customer pays you, the money does not hit your account the same day. Settlement is the process of moving the money from the card networks to your processor to your bank account, and it takes time. Most processors settle within 1 to 2 business days, meaning a payment you receive on Monday might land in your account on Wednesday. Some processors offer same-day settlement or next-day settlement for an extra fee (usually 0.5 to 1 percent of the transaction).

The processor holds the money in a reserve for a set period — often 7 to 30 days — before releasing it to you. This protects them if chargebacks come in later. Some processors require a rolling reserve, where they hold back a percentage of every transaction until the reserve reaches a target amount. Others use a fixed reserve, where they hold a lump sum upfront and release it after a set time. The longer the reserve period, the longer your money is tied up, which matters if you run on tight cash flow.

Payment methods and what each processor accepts

Not all processors accept all payment methods. Most accept Visa, Mastercard, American Express, and Discover. Some also accept ACH transfers (direct bank transfers), digital wallets (Apple Pay, Google Pay), or international cards. If you sell to customers outside the United States, check whether the processor handles currency conversion and at what rate — some processors mark up the exchange rate significantly.

Some industries have trouble finding processors at all. High-risk merchants — including online gambling, adult services, CBD products, and some financial services — are turned down by mainstream processors because of regulatory or chargeback risk. Specialized processors exist for these industries, but they charge much higher fees (4 to 8 percent or more) and may require a reserve or personal may provide.

Comparing processors: what to look at

When you are choosing a processor, compare the total cost, not just the per-transaction rate. Calculate what you would pay per month based on your actual transaction volume and average ticket size. A processor with a 2.5 percent rate plus a $20 monthly fee is cheaper than one with 2.2 percent and a $50 monthly fee if you process less than $2,000 a month, but more expensive if you process $10,000 a month.

Look at the contract terms. Some processors lock you in for a year and charge a penalty if you leave early. Others month-to-month with no penalty. Check the settlement time — if you need cash fast, next-day settlement matters even if it costs more. Ask about chargeback rates and what happens if yours gets too high; some processors will close your account if chargebacks exceed 1 percent of your volume. Finally, test their customer support — call with a question and see how long you wait. If something goes wrong with a payment, you need to reach someone quickly.

Frequently Asked Questions

Can I negotiate interchange fees with my processor?

No. Interchange fees are set by Visa, Mastercard, American Express, and Discover and are the same everywhere. What you can negotiate is the processor's markup on top of interchange. Some processors offer better markup rates if you process high volume or agree to a longer contract.

What is the difference between a payment gateway and a payment processor?

A payment gateway is the technology that encrypts card data and sends it to be processed. A payment processor is the company that actually moves the money. Some companies do both; others specialize in one. If you use a separate gateway and processor, you pay fees to both.

Why do some processors charge different rates for different card types?

Card networks set different interchange rates based on the card's features. A rewards card costs more to process than a basic card because the issuing bank pays rewards to the cardholder. Business cards and corporate cards also cost more. Your processor passes these costs to you, though some offer flat-rate pricing that averages them out.

What happens if I get too many chargebacks?

If your chargeback rate exceeds the processor's threshold (usually 1 percent of transactions), they may freeze your account, require a higher reserve, or close your account entirely. You can dispute chargebacks, and if you win, the transaction is reversed. Keep detailed records of orders and communications to fight chargebacks you believe are invalid.

Is it cheaper to use a payment aggregator or get a merchant account?

For low volume (under $1,000 a month), an aggregator is usually cheaper and faster to set up. For higher volume, a merchant account with a lower-cost processor saves money over time. Calculate your monthly fees based on your actual transaction volume to compare.