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Rastislav ₡ORE
Rastislav ₡ORE

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Why QR Banking Transfers Break Internationally — and Why `payto://bic` Fixes It

#payto #bic #money #fintech

Most banking QR systems were designed for domestic payment networks. They work well inside one country or one regional banking area, but they start failing once you move into international transfers, correspondent banking, or cross-border fintech apps like Revolut.

The newer payto:// standard changes that by introducing universal payment links for bank transfers.

Instead of proprietary QR payloads, payto:// creates interoperable payment URIs that can work across browsers, wallets, banking apps, and international SWIFT rails.

This article explains:

  • how traditional banking QR systems work
  • why they fail internationally
  • limitations of Pay by Square and EPC QR
  • why payto://bic matters
  • how to construct international payment URIs
  • how to generate QR codes
  • how to create deeplinks and payment buttons
  • how apps like Revolut could support it

The Problem with Existing Banking QR Systems

Most QR banking standards are local by design.

System Region International? Notes
EPC QR / GiroCode EU SEPA Partial Mainly SEPA-only
Pay by Square Slovakia No Slovak banking ecosystem
Swiss QR Bill Switzerland Limited Swiss payment rails
PIX QR Brazil No Domestic transfers
UPI QR India No Indian banks only
PromptPay Thailand No Thai-only

These systems work because banks inside one network agreed on:

  • one QR format
  • one clearing system
  • one routing method
  • one account structure

International banking does not work that way.

Example: Traditional EPC / SCT QR Payload

Older European banking apps often used EPC SEPA Credit Transfer payloads like this:

BCD
002
1
SCT
DEMOUS33XXX
ACME GLOBAL LTD
99887766554433221
USD

Invoice 2025-001
Intermediary: TESTGB2LXXX
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This format contains:

Field Meaning
BCD EPC QR identifier
002 Version
SCT SEPA Credit Transfer
DEMOUS33XXX BIC/SWIFT
ACME GLOBAL LTD Beneficiary
99887766554433221 Account number
USD Currency
Invoice 2025-001 Payment reference
TESTGB2LXXX Correspondent/intermediary bank

While this works for some banking apps, it has major limitations internationally.

Why Legacy Banking QR Codes Are Not Enough

The problems begin once the payment leaves the original banking region.

Many apps:

  • ignore intermediary bank information
  • only support SEPA transfers
  • cannot deep link into banking flows
  • cannot open from browsers
  • require manual copy/paste
  • cannot interoperate between wallets

Apps like Revolut internally support:

  • SWIFT transfers
  • BIC routing
  • multiple currencies
  • correspondent banks

But there is no universal payment URI standard connecting them.

That is the missing piece.

Why Pay by Square Is Still Regional

Pay by Square works extremely well in Europe because local banks standardized around one QR format.

But globally:

  • IBAN is not universal
  • account formats differ
  • correspondent routing differs
  • SWIFT instructions vary
  • intermediary banks may be required

This means a QR payload alone cannot reliably describe an international payment.

International Banking Is More Complex

A real international wire transfer may require:

Field Why It Matters
BIC/SWIFT identifies destination bank
Account number identifies recipient
Beneficiary name compliance/KYC
Currency settlement
Reference reconciliation
Intermediary bank routed SWIFT transfers
Fee mode SHA/BEN/OUR
Address regulatory checks

Most QR standards omit several of these.

That is why users still manually enter banking details for international transfers.

RFC 8905: Universal Payment URIs

RFC 8905 introduced a universal payment URI scheme:

RFC 8905 — payto URI

Basic structure:

payto://<network>/<target>?params
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Examples:

payto://iban/DE75512108001245126199
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or:

payto://bic/DEMOUS33XXX
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This changes payment handling completely.

Instead of QR codes encoding proprietary banking text formats, the payment becomes a universal URI.

Exactly like:

  • mailto:
  • tel:
  • bitcoin:

but for banking.

payto://bic Matters

BIC/SWIFT is globally recognized.

Unlike IBAN:

  • it works internationally
  • it supports SWIFT routing
  • it can represent correspondent banking flows
  • it is already understood by banks and fintech apps

This makes payto://bic ideal for cross-border transfers.

Minimal example:

payto://bic/DEMOUS33XXX
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With metadata:

payto://bic/DEMOUS33XXX
 ?receiver-name=ACME%20GLOBAL%20LTD
 &amount=USD:120
 &message=Invoice-2025-001
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Why This Helps Apps Like Revolut

Today the flow usually looks like this:

  1. scan QR
  2. manually copy details
  3. open banking app
  4. create SWIFT transfer manually
  5. paste fields one-by-one

With payto://bic:

  1. scan QR
  2. app opens automatically
  3. transfer form prefilled
  4. user confirms payment

This creates a real browser-native payment experience.

Constructing a payto://bic Transfer

Minimal 

payto://bic/DEMOUS33XXX
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With Amount 

payto://bic/DEMOUS33XXX?amount=USD:100
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Full International Example 

payto://bic/DEMOUS33XXX
  ?receiver-name=ACME%20GLOBAL%20LTD
  &account=99887766554433221
  &amount=USD:250
  &message=Invoice-2025-001
  &corr=TESTGB2LXXX
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This structure is:

  • human readable
  • QR compatible
  • browser compatible
  • deeplink compatible
  • extensible

Why Intermediary Banks Matter

One major weakness of traditional QR standards is correspondent routing.

For example:

Intermediary: TESTGB2LXXX
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This is critical for many international transfers.

Older QR systems often treat this as free-form text, making parsing unreliable.

payto://bic can preserve this structurally:

&corr-bank-bic=TESTGB2LXXX
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This makes routing deterministic and machine-readable.

Suggested Extended International Format

A practical SWIFT-compatible structure could look like:

payto://bic/DEMOUS33XXX
  ?account=99887766554433221
  &receiver-name=ACME%20GLOBAL%20LTD
  &amount=USD:100
  &message=Invoice-2025-001
  &corr-bank-bic=TESTGB2LXXX
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This is far more interoperable than opaque banking QR payloads.

Generating QR Codes

Because payto:// is just a URI, generating QR codes becomes trivial.

JavaScript Example 

import QRCode from "qrcode";

const uri =
  "payto://bic/DEMOUS33XXX?amount=USD:100";

QRCode.toCanvas(canvas, uri);
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Any QR library works.

Deeplinking From the Browser

This is where payto:// becomes powerful.

Simple Link 

<a href="payto://bic/DEMOUS33XXX">
  Pay via International Bank Transfer
</a>
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Triggering Native Apps

On mobile:

window.location.href =
  "payto://bic/DEMOUS33XXX?amount=USD:250";
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Apps registered for the payto:// protocol can intercept the payment request automatically.

Exactly how:

  • mailto:
  • tel:
  • bitcoin:

already work today.

Example UI

Modern implementations can generate:

  • QR codes
  • payment buttons
  • deeplinks
  • wallet passes
  • mobile payment previews

Recommended Architecture

Merchant Side

Generate:

payto://bic/...
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Store:

  • amount
  • currency
  • reference
  • branding
  • transfer metadata

Render:

  • QR code
  • deeplink
  • payment button
  • wallet pass

Wallet / Banking App Side

Register handler:

payto://
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Parse:

  • BIC
  • account
  • amount
  • reference
  • correspondent bank
  • fee settings

Then prefill the international transfer UI automatically.

Why This Is Better Than IBAN Alone

IBAN is regional.

BIC is global.

Many countries:

  • do not use IBAN
  • require correspondent banks
  • use local account formats
  • require extra routing instructions

payto://bic becomes:

  • rail-agnostic
  • internationally routable
  • wallet-friendly
  • browser-native

Why This Matters

Banking still lacks:

  • universal payment URLs
  • interoperable payment deeplinks
  • browser-native bank transfer flows

payto:// fills the same role for banking that:

  • mailto: did for email
  • tel: did for phones
  • bitcoin: did for crypto wallets

And payto://bic may finally make international bank transfers portable across:

  • wallets
  • banking apps
  • QR systems
  • fintech platforms
  • browsers

without requiring users to manually type SWIFT instructions again.

Try generate PayTo BIC yourself.

Libraries

References

All banking identifiers shown in this article are fictional examples for demonstration purposes only.

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