In its March 2022 position paper on 8-digit BINs, Visa reported that "tables purchased off the internet are roughly 30% accurate." If your checkout decides debit or credit, consumer or commercial, UK or foreign from a downloaded list keyed on six digits, that is the quality of data behind the decision.
The pages ranking for "8 digit bin" stop at the April 2022 deadline, some still in the future tense, and none maps BIN data to what payment APIs actually return. This guide does, along with the PCI limits by card length and the UK rules that depend on card type. Documentation was checked on 24 October 2026.
What Is an 8-Digit BIN, and Is a BIN the Same as an IIN?
In practice, yes. IIN (issuer identification number) is the term ISO/IEC 7812-1 uses, BIN (bank identification number) is the older industry name, and the schemes use both. It is the leading digits of the card number, and it identifies the issuer and, through the scheme's tables, the card product.
The fifth edition of ISO/IEC 7812-1, published in January 2017, lengthened the IIN from six digits to eight. ISO's announcement gave one reason: "there is expected to be a shortage in the available supply of IINs." Every existing six-digit IIN became "a block of a hundred eight-digit IINs", and an issuer with an eight-digit IIN must issue card numbers of at least ten digits, with 19 still the maximum. The American Bankers Association is still the registration authority.
Two consequences matter to engineers. The card number does not get longer: Visa's FAQ says PANs "will remain the same at 16 digits", so the issuer prefix takes two digits from the account number. And six-digit BINs did not disappear. Issuers can keep them, split them or run both, so any system that assumes one fixed length is wrong for some share of cards.
When Did Visa and Mastercard Move to 8-Digit BINs?
Visa endorsed the standard in 2017 and named 22 April 2022 "its final effective date". From then, acquirers and processors had to support eight-digit issuing BINs. Issuers never had to migrate: Visa's requirements say they "have the option to expand any or all of their current six-digit issuing BINs".
According to Deloitte's 2020 readiness paper, Mastercard planned to issue eight-digit BINs after April 2022 with no end date for six-digit ones. Discover's September 2026 IIN table defines the IIN as "the first six (6) or eight (8) digits" and lists every range it carries, JCB and UnionPay included, in eight-digit form. American Express stays on 15-digit cards, which PCI still caps at first six, last four.
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About the Author
I'm Tom Wang, an AI Developer & Fintech Developer — building AI agents, crypto payment infrastructure, and cross-border payout systems with Rust, Go, and TypeScript. Based in London, UK.
Currently open to new opportunities in fintech, crypto payments, and AI agent engineering.
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