How it works
How BrainMerchant fits into your platform
Your customers pay inside your software. BrainMerchant, the payment gateway, sends each card or ACH bank payment over the right network for processing.
What your platform decidesBefore the first payment runs
- Payment methodsCard, ACH or both
- PlacementInvoices, checkout or statements
- Customer setupSign-up and verification under the provider’s rules
- AuthorizationsThe payer agrees in the right form
Both methods run through BrainMerchant
The payment path
How a payment moves through BrainMerchant
In the card and ACH payment flow, both kinds of payment start in your software and pass through the same gateway. They split at the network.
- Your customerChooses card or bank
- Your platformThe payment step inside your product
- BrainMerchantThe payment gateway
- Card networksFor card paymentsACH NetworkFor bank payments
- BanksFunds settle between banks
In your software. Your customer opens an invoice, a checkout or a statement in your product and chooses to pay by card or from a bank account. The payment then goes from your software to BrainMerchant.
At the gateway. BrainMerchant passes the payment on for processing over the card networks or the ACH Network, then returns the result to your platform. ACH is a US payment network, so the ACH side is for US bank accounts.
At the banks. Funds then settle between banks. When your customers are paid after that depends on their provider’s funding schedule.
Timing
Card and ACH run on different clocks
A card payment gets its answer up front. The issuer approves or declines it, the sale is captured, and funds then settle between the issuer and the acquirer.
An ACH debit pulls money from the payer’s account, and an ACH credit pushes money to the receiver. Each entry settles between banks on a date the rules allow, and the receiving bank can still return it afterward. As of October 2026, under Nacha rules (confirm the details with your provider or the rule source):
- A debit settles the next banking day, or the same day if it is sent as Same Day ACH.
- A credit can settle the same day, the next banking day or two banking days out.
- Most returns must reach the originating bank by the opening of business on the second banking day after settlement.
- An unauthorized debit to a consumer account can be returned for up to 60 calendar days after settlement.
Card paymentCard networks
- AuthorizeThe issuer approves or declines
- CaptureThe sale is confirmed
- SettleFunds move between banks
- FundThe merchant is paid on its provider’s schedule
ACH paymentACH Network
- AuthorizeThe customer authorizes the debit
- OriginateThe entry is sent in a batch
- SettleFunds move between banks
- Return windowMost returns arrive within two banking days
The parties
Who does what
Every payment in your software involves the same four parties, each with its own job.
Your platform
Owns the screens and the customer relationship. You decide which payment methods to offer and where payments appear in your product.
Your customers
The businesses or people who pay or get paid inside your software. Those who pay choose card or bank at the payment step.
BrainMerchant
The payment gateway between your platform and the payment networks. BrainMerchant processes credit card and ACH payments for software platforms.
Networks and banks
The card networks and the ACH Network carry each payment between banks: the payer’s card issuer or bank on one side, and the bank receiving the funds on the other.
Your platform’s role under the payment rules
Depending on how your platform handles payments, the payment rules can give it a role of its own. On the ACH side, as of October 2026, the Nacha Operating Rules set that role by whose name is on the agreement with the ODFI, the originating bank that sends entries into the ACH Network:
- Third-Party Sender, if your platform holds the ODFI agreement and sends entries for its customers.
- Third-Party Service Provider, if your customers hold the bank agreement.
- Nested Third-Party Sender, if your platform sends entries through another Third-Party Sender.
A Third-Party Sender carries duties of its own: see Third-Party Sender in the payments glossary, and confirm the details with your provider or the Nacha Operating Rules. We’ll walk you through where your platform fits. For the wider picture, see how embedded payments work for software platforms.
Four steps
Working with BrainMerchant, step by step
The first one is a conversation about your product.
Share how your platform works
Describe your product, who uses it and which payments happen in it or outside it today.
Map card and ACH flows
Together we take each payment your customers make, match it to card, ACH or both, and note the network rules that apply.
Plan the integration together
We agree with you on how your software connects to BrainMerchant for card and ACH payments.
Go live with payments
Once your platform is approved and a written agreement is signed, the payment step opens to your customers, and each card or ACH payment they make runs through BrainMerchant.
Before the call
What to bring to the first conversation
You don’t need a finished plan. Rough answers to these questions are enough for a first call.
- What your customers sell or bill for, such as rent, tuition, services or memberships.
- Whether payers are consumers or businesses, because that changes which ACH SEC codes (Standard Entry Class codes) and return windows apply.
- Your expected card and ACH mix, even as a rough split.
- Typical and largest payment sizes, so the conversation covers the payments your customers actually make.
- One-time or recurring payments, and how often the repeat payments happen.
- How your customers get paid today, inside your product or somewhere else.
- Where payments should appear in your product, screen by screen.
- Which payment provider your customers use today, if any.
Questions
Common questions about how it works
Do my customers leave my software to pay?
Payments happen within your product’s flow. How the payment step is built, and what that means for your PCI scope, is planned with you on a call.
Who decides which payment methods appear?
Your platform does. You choose whether to offer cards, ACH or both, and where each one appears: on invoices, at checkout or on statements. How your customers are signed up and verified, and how payers give their authorization, follow the payment rules, and we plan both with you on a call. Read more about credit card processing for platforms and ACH payment processing for platforms.
Is there a technical integration?
Yes. A payment integration for software platforms connects your software to the gateway, here BrainMerchant, so card and ACH payments can run inside it. How that connection is built depends on your product and your payment flows, so we plan it with you on a call. It helps to tell us how your software is built.
What happens after I contact you?
We aim to reply by email and set up a conversation about your platform. That call is the first of the four steps above. You can reach us through the contact form or by email:
Next step
See how card and ACH payments would work in your product
Start with a short note about your software and who pays inside it. The list of what to bring above is a good outline.