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BS ISO IEC 07812 — Identification Cards Identification of Issuers (IIN) Standard Series
Identification cards — Identification of issuers
BS ISO/IEC 7812-1:2017 · BS ISO/IEC 7812-2:2017
BS ISO/IEC 7812-1:2017 · BS ISO/IEC 7812-2:2017
💳 BS ISO/IEC 7812 is the joint ISO/IEC standard on identification cards — identification of issuers, published in the United Kingdom by BSI. The series defines the numbering system and registration procedures used to identify the issuer of an identification card (such as bank cards, payment cards, stored-value cards and identity cards). Part 1 specifies the numbering system, while Part 2 specifies the application and registration procedures. It underpins the global allocation of the Issuer Identification Number (IIN, formerly the Bank Identification Number, BIN), and is the basis for card-number validation (e.g. the Luhn algorithm) and transaction routing. UK participation was coordinated by Technical Committee IST/17 (Cards and personal identification).
💡 The IIN (formerly BIN) is the “identity prefix” of an identification card: the first six digits of the card number uniquely identify the issuing institution, enabling transactions to be routed correctly to the issuer for authorisation, clearing and settlement — a cornerstone of the global payment system.
1. Background and Positioning of the Standard Series 📌
Identification cards (especially bank and payment cards) need to be uniquely identified worldwide. With many issuers, transactions cannot be routed correctly without uniform numbering rules. ISO/IEC 7812 was developed for this purpose: it defines the format of the Primary Account Number (PAN), specifies the structure and allocation mechanism of the Issuer Identification Number (IIN), and establishes a global IIN registration system managed by a registration authority. Parts 1 and 2 were published as fifth editions in 2017, superseding earlier versions.
The standard works alongside ISO/IEC 7810 (physical characteristics) and ISO/IEC 7813 (financial transaction cards) to form the foundation of the identification card series. For issuers, card schemes, acquirers and payment service providers, correctly understanding and applying ISO/IEC 7812 is a precondition for correct transaction identification and routing.
2. Standard Series Structure and Document List 📋
| Standard | Title | Content Focus |
|---|---|---|
| BS ISO/IEC 7812-1:2017 | Identification cards — Identification of issuers — Part 1: Numbering system | Specifies the PAN format, IIN structure, field meanings and numbering rules |
| BS ISO/IEC 7812-2:2017 | Identification cards — Identification of issuers — Part 2: Application and registration procedures | Specifies the application, approval and registration procedures for IINs and approval criteria |
⚠️ Parts 1 and 2 are closely related: Part 1 defines what the number looks like, while Part 2 defines how to obtain and register it. Applying for a new IIN must follow the procedures in Part 2 and use the rules in Part 1.
3. Part 1 — Numbering System 🔢
BS ISO/IEC 7812-1:2017 defines the Primary Account Number (PAN) format, typically 16 digits (varying from 13 to 19 depending on the card scheme), structured as follows:
- Issuer Identification Number (IIN): the first six digits of the PAN (extendable in some schemes), uniquely identifying the issuer. The standard specifically addresses the handling of IINs beginning with “00”.
- Account number: the digits after the IIN, allocated by the issuer, identifying the cardholder’s specific account.
- Check digit: the last digit of the PAN, used to validate the card number (typically based on the Luhn algorithm) and prevent entry and transmission errors.
The standard also specifies PAN encoding requirements, length conventions and related term definitions, ensuring consistency across card schemes and issuers. For technical developers, IIN recognition and card-number validation are both based on this part.
4. Part 2 — Application and Registration Procedures 📝
BS ISO/IEC 7812-2:2017 specifies the application procedures for the assignment of a single IIN or a block of IINs, including applicant qualification requirements, application materials and the workflow. The standard clarifies the criteria for approval of an application, distinguishing the cases of a “single IIN” and a “block of IINs”, and specifies the duties of the registration authority. Key points include:
- Applicant eligibility: only institutions that meet conditions and genuinely need to issue cards may apply for an IIN.
- Review and assignment: the registration authority reviews and assigns a unique IIN per the standard procedure, ensuring global uniqueness.
- Block assignment: for institutions requiring multiple IINs, blocks of numbers are assigned and their use managed according to the rules.
- Records and queries: the registration authority maintains the IIN registry for parties to look up and verify.
This part provides a unified, transparent operating rule for the global IIN registration system, and is the institutional foundation of an orderly payment card industry.
5. Engineering and Implementation Practice 🛠️
- 📋 Issuer application: new issuers apply to the registration authority for an IIN per Part 2 procedures and follow Part 1 numbering rules.
- 🔗 Routing and recognition: transaction processing systems identify and route the issuer based on the IIN within the PAN, parsing the card-number fields strictly per the standard.
- 🧪 Validation implementation: implement Luhn and similar validation algorithms to verify card-number validity at entry and transmission, reducing error rates.
- 🔒 Security and compliance: manage IIN and card-number data securely and comply with requirements such as PCI DSS.
🚨 Card-number recognition errors lead to misrouting, chargebacks and even financial risk. System implementations must parse the PAN’s IIN, account number and check digit strictly per ISO/IEC 7812-1 and ensure the validation algorithm is correct, preventing transaction failures from field-boundary misalignment.
6. Frequently Asked Questions ❓
Q1: What is the relationship between IIN and BIN?
IIN (Issuer Identification Number) is the formal name in ISO/IEC 7812; BIN (Bank Identification Number) is a long-standing banking colloquialism. They are essentially the same — the first six digits of the card number identifying the issuer.
IIN (Issuer Identification Number) is the formal name in ISO/IEC 7812; BIN (Bank Identification Number) is a long-standing banking colloquialism. They are essentially the same — the first six digits of the card number identifying the issuer.
Q2: How do the two parts divide the work?
Part 1 specifies the numbering system (PAN format, IIN structure, check digit); Part 2 specifies the application and registration procedures (how to obtain an IIN).
Part 1 specifies the numbering system (PAN format, IIN structure, check digit); Part 2 specifies the application and registration procedures (how to obtain an IIN).
Q3: Is a PAN always 16 digits?
No. PAN length is defined by the card scheme, commonly 13 to 19 digits, with the IIN as the first six digits, the last digit as the check digit, and the account number in between.
No. PAN length is defined by the card scheme, commonly 13 to 19 digits, with the IIN as the first six digits, the last digit as the check digit, and the account number in between.
Q4: Who registers IINs?
ISO/IEC 7812 designates a registration authority responsible for IIN assignment and registry maintenance; card schemes and issuers apply through its procedures.
ISO/IEC 7812 designates a registration authority responsible for IIN assignment and registry maintenance; card schemes and issuers apply through its procedures.
Q5: What does the check digit do?
It validates card-number integrity, detecting entry or transmission digit errors (omissions, transpositions), typically computed with the Luhn algorithm.
It validates card-number integrity, detecting entry or transmission digit errors (omissions, transpositions), typically computed with the Luhn algorithm.