You are checking out of an online store.
Below the familiar options—“Visa,” “Mastercard,” and “Apple Pay”—there is a new button. It says: “Pay with Bank.”
You click it. You are temporarily redirected away from the store and into a secure portal hosted directly by your actual bank. You log in there, approve the exact amount, and are instantly sent back to the store. The checkout is complete.
You never typed your bank password into the merchant’s website. The merchant never saw it. The merchant never touched your money directly.
Instead, money moved directly between your bank account and the merchant’s bank account using the domestic banking infrastructure, without a card network sitting in the middle.
This is the world of Account-to-Account (A2A) payments, powered by Open Banking. It is the most direct threat the legacy card networks have ever faced.
1. The Core Concept: Cutting Out the Middlemen
For decades, if you wanted to pay a merchant online, you had to route the transaction through a middleman. You used a card network (Visa/Mastercard) or a digital wallet (PayPal). These middlemen provided the security, the connectivity, and the user experience—but they charged a massive premium for it.
Open Banking flips this model. It provides a secure, standardized way for a merchant’s app to talk directly to your bank’s servers. (Note: While the term “Open Banking” technically also allows apps to read your financial data for budgeting, its most disruptive financial impact by far is enabling these direct A2A payments).
Instead of the merchant saying, “Charge this card,” the merchant says, “Ask the customer’s bank to send us money.”
Because there is no card network taking a cut, the merchant fees for A2A payments are often 60% to 80% cheaper than credit cards (typically around 0.5% to 0.8%, compared to 2.5%+ for credit).
2. The Participants
An A2A payment requires a different cast of characters than a card transaction.
- The Consumer: The person paying, who holds an account at a traditional bank.
- The Merchant: The business receiving the funds directly into their bank account.
- The Open Banking Provider (The Aggregator): Companies like Plaid, Trustly, or Tink. They are the bridge. A merchant doesn’t want to build custom connections to 10,000 different banks. The aggregator builds the connections once, and the merchant plugs into the aggregator via a single API.
- The Consumer’s Bank: The financial institution that holds the funds, verifies the user, and executes the payment instruction.
- The Domestic Payment Rail: The underlying pipe that actually moves the money. Examples include ACH, FedNow, RTP, SEPA, Faster Payments, UPI, or Pix. Open Banking is the doorway; the domestic rail is the highway.
3. The Magic Trick: Tokenized Consent
The biggest fear of A2A payments is security. How can a merchant pull money from your account without seeing your credentials?
The answer is Tokenized Consent, heavily modeled on how you log into a third-party app using “Log in with Google.”
Think about what happens when you use “Log in with Google” on a new app. You type your Google password into Google’s website, not the new app’s website. The new app just receives a digital green light saying, “This person is verified.”
When you click “Pay with Bank,” the exact same thing happens:
- The merchant redirects you to a secure portal hosted by your actual bank.
- You log in directly with your bank using whatever security your bank normally requires for its website—whether that is a password and an SMS code, or a biometric scan like FaceID. (Unlike Apple Pay, where FaceID unlocks a credit card token on your phone, here it is simply acting as the login mechanism for your bank’s website).
- Your bank issues a digital “token”—a temporary VIP pass that says: “This user has authorized this specific merchant to move exactly $45.00 one time.”
- The merchant receives the token. They never saw your login screen. They only have permission to execute that single transaction.
4. The Transaction Lifecycle
An A2A payment operates on a completely different flow than a card network. It relies on upfront consent rather than post-purchase authorization.
Phase 1: Initiation and Consent
You click “Pay with Bank.” The merchant app talks to the Open Banking aggregator, which generates a secure link to your bank. You are redirected to your bank’s interface, authenticate your identity, and approve the exact amount. The bank generates the consent token and sends it back to the merchant.
Phase 2: The Payment Instruction
The merchant receives the token. They send a message to the aggregator saying: “Here is the token. Please tell the bank to execute the payment.”
Phase 3: Bank Verification
The aggregator forwards the instruction to your bank. Because you already authenticated and approved the transaction in Phase 1, the bank doesn’t need to do a complex fraud check on the merchant. It simply verifies the token is valid, checks that you have sufficient funds, and prepares to move the money.
Phase 4: Movement on the Rail
The bank executes the payment on the underlying domestic payment rail.
- If it is an instant rail (like SEPA Instant, Pix, or FedNow), the merchant gets the money in seconds.
- If it is a batch rail (like ACH), the merchant gets the money in 1 to 2 business days.
Summary of the Flow:
- Consent: You securely log into your bank’s portal and approve the exact amount; the bank issues a token.
- Instruction: The merchant sends the token to the aggregator.
- Verification: The bank verifies the token and the funds.
- Movement: Money moves directly between the accounts via a domestic payment rail.
5. The Global Translation Guide
The adoption of Open Banking looks vastly different depending on the region, dictated entirely by government regulation.
- Europe (PSD2): The pioneer. The European Union passed a law (PSD2) legally forcing banks to open up their data to third-party aggregators via secure APIs. Combined with their instant SEPA rail, Europe has a thriving A2A ecosystem where consumers routinely pay for e-commerce directly from their bank accounts.
- United States (Plaid / FDX): The US is playing catch-up. Because the US has no federal mandate forcing banks to open their data, A2A relies on private companies like Plaid. Historically, Plaid had to “screen scrape” (log in as you and read the screen). Now, they are transitioning to true API tokenization, but the system remains highly fragmented compared to Europe.
- Markets That Skipped It (India/Brazil): It is worth noting that some markets bypassed Open Banking APIs entirely. As we covered in our Real-Time Payments article, countries like India (with UPI) and Brazil (with Pix) built unified, instant, public rails. Because the government gave everyone a single, standard payment ID, they didn’t need private companies to bridge the gap between banks.
6. The Economics: Why Merchants Are Pushing It
For merchants, A2A is a financial necessity.
On a $100 item paid with a premium rewards credit card, the merchant might lose $3.00 to interchange fees. On a $100 item paid via A2A, the merchant might only lose $0.60.
For large, low-margin businesses (like airlines, utilities, or gig-economy platforms paying out contractors), saving 2% on every transaction translates to hundreds of millions of dollars in recovered revenue.
This is why companies like Uber, Amazon, and major airlines are aggressively building “Pay with Bank” buttons into their checkout flows. They are willing to offer you a discount to choose A2A, because they keep so much more of the sale.
7. The Friction: Why Cards Still Win
If A2A is so much cheaper, why isn’t everyone using it?
- The Dispute Problem (The Card Superpower): If you buy a shirt online with a credit card and it never arrives, you click a button and the bank instantly takes the money back from the merchant (a chargeback). With A2A, the money is already gone from your account. Getting it back requires navigating the merchant’s customer service. Consumers love the protective shield of credit cards.
- The UX Friction: Clicking “Pay with Apple Pay” takes one second. Clicking “Pay with Bank” often requires redirecting to a bank login page, waiting for a text message code, and redirecting back. The user experience is currently clunky.
- The Subscription Problem: A2A is great for one-time purchases. But setting up recurring payments (like Netflix) directly from a bank account is technically difficult because bank tokens expire for security reasons. The industry is working on “Variable Recurring Payments” (VRPs) to fix this, but it is not yet standard.
8. The End of the Plastic Intermediary
Account-to-Account payments represent the purest form of digital money movement. It is simply one database at a bank talking to another database at a bank.
Open Banking provided the secure doorway. Domestic payment rails provided the highway.
Cards will not disappear tomorrow. They will survive because of their rewards programs, their universal acceptance, and their ironclad consumer protection policies.
But for the heavy, high-volume plumbing of global e-commerce and B2B payments, the era of routing everything through a 2% card network is coming to an end. The banks are finally talking to each other, and the intermediaries are being cut out.