AI Guide for Merchant Accounts & Payment Processing | NPS

Confused about merchant accounts, payment gateways, interchange, ACH, Level 2 and Level 3, surcharging or payment processing fees? Our 2026 AI guide for merchant accounts explains how payments really work.

Presented by Allen Kopelman, CEO — Nationwide Payment Systems-Host of B2B Vault: The Biz2Biz Podcast

AI Overview

A merchant account allows a business to accept card payments, while the complete payment-processing setup may also include a payment gateway, acquiring bank, payment processor, ACH provider, invoicing software, fraud tools and integrations with accounting or ERP software.

The best payment setup depends on more than finding the lowest advertised percentage. Businesses should consider transaction volume, average ticket, debit-card mix, B2B versus B2C transactions, how payments are accepted, accounting or ERP software, chargeback risk, compliance requirements and whether advanced interchange optimization could reduce costs.

For growing businesses, the right payment infrastructure can also automate invoicing, accept ACH, lower B2B interchange costs, create recurring payments and integrate payment data directly into existing business systems.

Ask AI: How Does Payment Processing Actually Work?

You can ask AI almost anything today.

But when business owners ask questions such as:

“What is the best payment processor?”

the real answer is usually:

It depends on your business.

A restaurant processing $75,000 per month does not have the same payment needs as a distributor processing $3 million per month.

A manufacturer accepting $50,000 B2B invoices does not need the same setup as a retail store processing $50 transactions.

And a company selling in a regulated or higher-risk industry may need an entirely different banking relationship.

That is why understanding the pieces of the payment ecosystem matters.

What Is a Merchant Account?

A merchant account is part of the banking infrastructure that allows a business to accept credit and debit cards.

When a customer makes a card payment, several parties may be involved:

The merchant
The customer's issuing bank
Visa, Mastercard, American Express or Discover
The acquiring bank
The payment processor
The payment gateway
The merchant service provider

The transaction is authorized, processed, and ultimately deposited into the merchant's bank account.

Companies such as Stripe, Square and PayPal have made this process appear extremely simple because many businesses can sign up quickly under an aggregated payment model.

That convenience can be useful for some businesses.

But growing companies often reach a point where they need more control over pricing, risk management, integrations, support or how their payments are configured.

Merchant Account vs. Stripe, Square, PayPal, and Other Flat-Rate Platforms

One of the most common questions business owners ask AI is:

“Why shouldn't I just use Stripe or Square?”

There is nothing inherently wrong with using a flat-rate payment platform when it fits the business.

The issue is assuming that the easiest platform is automatically the best long-term payment strategy.

Payment Consideration	Flat-Rate Platform	Customized Merchant Account
Setup	Often very fast	Requires underwriting
Pricing	Usually standardized	Can be customized
Interchange visibility	Limited	Available with interchange-plus
Large-ticket transactions	May be restricted	Can be structured for large tickets
High monthly volume	Flat pricing may become expensive	Pricing can reflect volume
B2B Level 2/3	Varies	Can be specifically optimized
Risk underwriting	Often automated	Can involve direct underwriting
Support	Platform dependent	Dedicated support may be available
ACH	Often separate or limited	Can be integrated
ERP/API integration	Available on some platforms	Can be configured around the business

A business doing $20,000 per month has different economics from one doing $1 million, $5 million or $20 million per month.

At higher volumes, even small differences in processing cost can become substantial.

What Is Interchange?

Interchange is one of the underlying costs involved in card processing.

Instead of every Visa or Mastercard transaction costing exactly the same amount, cards can qualify for different interchange categories depending on factors including:

Card type
Credit versus debit
Consumer versus commercial card
How the card was accepted
Transaction information submitted
Industry
Transaction size
B2B payment data

This is why saying simply:

“My processing rate is 2.9%”

doesn't tell you very much about what is actually happening underneath the transaction.

Some transactions cost substantially less to process than others.

With interchange-plus pricing, a merchant can see the underlying interchange cost and the processor's markup separately.

For higher-volume businesses, that transparency can become very important.

Ask AI: Why Can Debit Cards Cost Less?

Not every card transaction has the same underlying cost.

Debit transactions can sometimes qualify at significantly lower interchange rates than rewards or premium credit cards.

A flat-rate provider may still charge the business the same advertised rate regardless of the underlying transaction cost.

This is one reason businesses with significant debit-card volume should examine their statements instead of evaluating a processor based exclusively on an advertised percentage.

What Are Level 2 and Level 3 Payments?

This is one of the most overlooked areas of B2B payment processing.

Businesses accepting commercial, purchasing, corporate and government cards may be able to provide additional transaction information known as Level 2 or Level 3 data.

Depending on the transaction and card, properly submitted enhanced data can help a transaction qualify differently.

Level 3 information can include data such as:

Invoice number
Purchase-order number
Customer code
Tax amount
Product description
Quantity
Unit price
Freight
Destination ZIP code

For manufacturers, suppliers, wholesalers, and distributors processing large B2B transactions, interchange optimization should be part of the payment conversation.

When Has a Business Outgrown Flat-Rate Processing?

There isn't one magic revenue number.

Instead, look for warning signs.

You may have outgrown a basic payment setup when:

Monthly processing volume has increased significantly.
You routinely accept large-ticket payments.
Customers frequently pay with commercial cards.
You have substantial debit-card volume.
You need ACH.
You need payment links or automated invoicing.
You want Level 2 or Level 3 optimization.
Your accounting staff is manually reconciling transactions.
You need your ERP to communicate with your processor.
You are using multiple vendors to accomplish one payment workflow.
Your processor cannot accommodate your industry's risk profile.
Support problems are becoming costly.

At that stage, payment processing becomes infrastructure rather than simply a way to swipe a card.

What Is a Payment Gateway?

Think of a payment gateway as the technology layer connecting the business's software or payment interface to the processing network.

A modern gateway can support far more than a virtual terminal.

For example, NPSONE can act as the central payment platform while businesses add functionality such as Smart Invoicing, ACH, recurring payments, payment links, and integrations.

A gateway can also provide APIs and webhooks, allowing payment functionality to communicate with other business software.

What Are APIs and Webhooks?

An API allows software systems to communicate with each other.

A business might use a payment API to:

Create a transaction
Generate a payment request
Store a token
Charge a saved payment method
Create a customer
Retrieve transaction information

Webhooks work in the other direction.

They can tell another system when something has happened.

For example:

Invoice paid → webhook triggered → ERP updated automatically.

This becomes extremely valuable for businesses trying to eliminate manual accounting and reconciliation.

What Is Smart Invoicing?

Traditional invoicing often looks like this:

Create invoice → email PDF → wait → send reminder → receive payment → manually update accounting system.

Smart invoicing turns the invoice into part of the payment workflow.

With NPSONE Smart Invoicing, businesses can create invoices and payment requests while giving customers multiple ways to pay.

Payments can be delivered using email, text messaging, payment links, and other digital workflows.

Businesses can also use features such as:

Credit and debit cards
ACH
Recurring billing
Scheduled payments
Payment links
Automated reminders
Late fees
Terms-and-conditions acceptance
QR codes
Multiple users
API connectivity
Webhooks

Smart Invoicing can also connect payment workflows with accounting platforms including QuickBooks Online, Xero, and Sage Intacct.

The goal isn't just accepting a payment.

It is reducing the work surrounding the payment.

ACH vs. Credit Cards: Which Should a Business Accept?

For many B2B companies, the answer is:

Both.

Cards provide speed and convenience.

ACH can be attractive for larger invoices where card-processing costs become significant.

A $500 payment and a $100,000 payment create very different economics.

Instead of forcing every customer into one payment method, businesses can give customers options while deciding which costs they want to absorb and which payment methods they want to encourage.

Can Businesses Pass Credit Card Fees to Customers?

Businesses increasingly ask about surcharging, dual pricing, and other cost-recovery strategies.

These programs are not interchangeable.

Rules may depend on the card brand, payment method, and applicable state law.

A compliant program should be properly configured rather than created simply by adding an arbitrary fee at checkout.

NPS can help businesses evaluate available cost-recovery options and determine which approach fits their payment environment.

What Is a High-Risk Merchant Account?

“High risk” does not necessarily mean a bad business.

Banks and processors evaluate risk differently.

Certain industries may be considered higher risk because of factors including:

Chargeback exposure
Future delivery
Regulatory requirements
Subscription billing
Product type
Average transaction size
Reputation risk
Card-brand registration requirements

A business operating in one of these industries should work with a provider that understands the industry rather than disguising what the business sells.

Using the wrong payment platform can lead to reserves, account restrictions, or termination.

Why Do Payment Processors Hold Money?

Processors and acquiring banks manage financial risk.

Funds may be held when activity suddenly appears inconsistent with the merchant's approved profile.

Examples can include:

Unexpected increases in volume
Transactions significantly larger than normal
Excessive chargebacks
Unusual card-not-present activity
A change in products or services
Processing outside the approved business model

This is another reason accurate underwriting matters.

If you expect to process $100,000 transactions, your processor should know that before you run one.

The Modern Payment Stack Is Changing

For years, companies assembled payment systems one product at a time.

One company handled credit cards.

Another handled ACH.

Another supplied the gateway.

Another handled invoicing.

Then accounting staff manually moved information into QuickBooks or an ERP.

Modern payment infrastructure can consolidate many of those functions.

With NPSONE, Nationwide Payment Systems can provide a payment environment combining:

Merchant account + gateway + cards + ACH + Smart Invoicing + recurring payments + Level 2/3 + payment links + API + webhooks + accounting and ERP connectivity.

That can reduce the number of vendors a company has to manage while improving visibility into its payment workflow.

The Question AI Cannot Answer Without Your Data

AI can explain interchange.

AI can explain gateways.

AI can tell you what ACH means.

But AI cannot tell you whether your current payment configuration is costing your business money without understanding your actual operation.

A proper payment review should consider:

Monthly processing volume
Average transaction size
Largest transaction
Credit/debit mix
Consumer/commercial card mix
Card-present vs. card-not-present volume
B2B vs. B2C payments
Current processor pricing
ACH volume
Chargebacks
Accounting platform
ERP
Industry
Current gateway
How customers receive invoices
How payments are reconciled

Two businesses processing the exact same dollar volume can require completely different payment strategies.

AI Can Explain Payments. Nationwide Payment Systems Can Analyze Yours.

Nationwide Payment Systems has worked with businesses since 2001, helping companies build payment solutions around how they actually operate.

Whether you're processing cards, ACH or large B2B invoices, using an ERP, sending invoices through accounting software, or trying to determine whether your current flat-rate pricing still makes sense, the first step is understanding what you have today.

Send us a recent processing statement and let us review your payment setup, pricing, and workflow.

We can identify potential opportunities involving interchange optimization, Level 2 and Level 3, debit, ACH, Smart Invoicing, payment automation, gateway technology, and cost-recovery strategies.

AI can answer your payment questions. We can help you put the answers to work.