Most people have never heard of an IIN. But every card payment you make depends on one.
What Is an IIN?
An Issuer Identification Number (IIN), formerly known as a BIN (Bank Identification Number), is the first 6-8 digits of your card number. When you tap your card at a terminal, those digits tell the payment system who issued the card and where to route the transaction.
Visa's IINs start with 4. Mastercard's start with 5. American Express starts with 3.
These numbers are assigned by ISO (the International Organization for Standardization) through the ISO/IEC 7812 standard. The same body that standardizes everything from paper sizes to quality management.
Why It Matters
Without an IIN, you can't issue cards that work in the existing payment ecosystem. Every terminal, every acquirer, every payment processor uses the IIN to route transactions.
Getting one means you're recognized as a card issuer at the same level as Visa and Mastercard. You're in their routing tables. Terminals read your cards.
How We Got Ours
OpenPasskey applied directly to ISO for our own IIN range. This gives us capacity for up to 99 billion unique card numbers.
With our IIN, any acquirer can add us to their routing table in approximately one day. Merchants don't need new terminals. They don't need new software. Their existing EMV terminal reads our card just like it reads a Visa.
What Makes Our Card Different
Our card uses the same EMV contactless standard that Visa and Mastercard use. The physical card runs a custom applet on a Java Card chip.
But instead of Visa's legacy 3DES encryption, our card signs with P-256 ECDSA (the same elliptic curve used in TLS, Apple's Secure Enclave, and modern EMV chips). This is cryptographically stronger and more efficient.
The Settlement Layer
Here's where it gets interesting. Visa settles through a network of banks over 2-3 business days. We settle on-chain:
- Card taps terminal, signs transaction with P-256
- Signature verified on-chain via RIP-7212 precompile on Base L2
- AUD stablecoin transfers to merchant's
CREATE2receiver - Merchant gets AUD in their bank account
Settlement in seconds. Not days.
The Numbers
- 3,200+ wallet users across 20+ Sydney cafes
- 45,509 total transactions, AU$66K volume
- 4.5x industry average week-12 retention
- 3 people, 10 months, zero external funding
- Blackbird Giants Cohort 11 (Canva's earliest investor)
- Base ecosystem grant recipient
Why Now?
Australia's RBA just banned card surcharges (effective October 2026). Merchants still pay 0.3-0.8% on every tap. They just can't pass it on anymore.
With our own IIN and a settlement layer that removes the intermediaries, we're offering merchants a way to actually eliminate that cost.
Same tap. Different rails. No banks.
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